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Kalyn's Kitchen

Low-Carb Balsamic and Onion Pot Roast (How to Make Pot Roast in a Slow Cooker)

Low-Carb Balsamic and Onion Pot Roast is a delicious dinner that’s made in the Crockpot, and this is also gluten-free. This post also gives tips for How to Make Pot Roast in a Slow Cooker. Use Slow Cooker Recipes to find more recipes like this one.

PIN Low-Carb Balsamic and Onion Pot Roast to make it later!

Low-Carb Balsamic and Onion Pot Roast found on KalynsKitchen.com

When my friend Bonnie told me she had made this Low-Carb Balsamic and Onion Pot Roast and liked it, I immediately realized I wanted to make it again just so I could take better photos! Bonnie was kind enough to say that she didn’t think the old photos were that bad, but trust me, these updated photos give you a much better idea of what a tasty recipe this is!

This pot roast is just the thing to cook on low all day in the slow cooker while you’re at work, and dinner will be ready when you get home. Check out Ten Low-Carb and Keto Slow Cooker Recipes with Beef for more ideas for more delicious slow cooker dinners!

Tips for Making Pot Roast in the Slow Cooker:

I’m not a pot roast expert, but I’ve made pot roast in the Crockpot enough times to have strong opinions about how it should be done. There are three things I think are important to remember.

  1. First, Brown the meat well before you put it in the Crockpot because browning creates flavor.
  2. Second, don’t use too much liquid for any crockpot cooking, but especially for pot roast.
  3. Third, be sure there is plenty of flavor in the liquids you’re using. All day cooking can make foods bland if there isn’t a flavorful liquid.

I’m using all those tricks in this pot roast recipe. If there are others reading this who use a slow cooker to make pot roast, chime in with some comments about good tips for making pot roast in the Crockpot.

Low-Carb Balsamic and Onion Pot Roast process shots collage

Steps for Making Low-Carb Balsamic and Onion Pot Roast:

(Scroll down for complete printable recipe including nutritional information.)

  1. I used a very thick chuck roast from Costco; here’s how my roast looked after I trimmed it. (I had to cut it in half to get it to fit in my Crockpot.) I save all the scraps in a container which goes in the freezer, and then use them to make beef stock.
  2. Rub meat on both sides with steak seasoning and black pepper, then brown the roast well.
  3. In a small saucepan, reduce 1 cup beef stock to 1/2 cup.
  4. While the meat browns, cut the onions and put them in the Crockpot.
  5. When the meat is brown put it in slow cooker on top of the onions, then deglaze the pan with 1/4 cup water, scraping off all browned bits, and add to reduced beef stock.
  6. Add balsamic vinegar and tomato sauce to beef stock and pour over pot roast.
  7. Cook on low 6-8 hours, until meat is tender.
  8. I drained all the liquid from the Crockpot and used a fat separator to remove the fat. (I reduced the amount in the recipe I’m giving you.)
  9. After the fat is removed, reduce the liquid by about 1/3 to make a sauce. You could thicken it, but I didn’t think it needed it.
  10. You might think they’d be too done from being in the Crockpot all that time, but the onions were delicious as well as the meat.

Make it a Low-Carb Meal:

This would taste great with Pureed Cauliflower with Garlic, Parmesan, and Goat Cheese for a low-carb meal.

More Tasty Beef Recipes for the Slow Cooker or Instant Pot:

Instant Pot Barbacoa Beef ~ Taste and Tell
Low-Carb Stuffed Peppers with Beef, Sausage, and Cabbage ~ Kalyn’s Kitchen
Slow Cooker Beef and Broccoli ~ Well Plated
Crockpot Recipe for Southwestern Pot Roast ~ Kalyn’s Kitchen
Instant Pot Beef Short Ribs ~ That Skinny Chick Can Bake
Green Chile Shredded Beef Cabbage Bowl ~ Kalyn’s Kitchen

Weekend Food Prep:

This recipe has been added to a new category called Weekend Food Prep  to help you find recipes you can prep or cook on the weekend and eat during the week!

Balsamic and Onion Pot Roast in the Crockpot

Balsamic and Onion Pot Roast in the Crockpot

Yield 6 servings
Prep Time 25 minutes
Cook Time 8 hours
Total Time 8 hours 25 minutes

This Low-Carb Balsamic and Onion Pot Roast is a deliciously and easy dinner that’s made in the Crockpot.


  • 4 pound boneless chuck roast, fat trimmed
  • 1 T steak rub (see notes)
  • black pepper to taste
  • 1 T olive oil (depends on your pan)
  • 1/4 cup water to deglaze pan
  • 2 large onions, peeled and thickly sliced
  • 1 cup beef stock, reduced to 1/2 cup (see notes)
  • 1/2 cup balsamic vinegar (see notes)
  • 1/2 cup tomato sauce


  1. Trim as much fat as you can from roast, and cut if necessary to fit into Crockpot. Rub meat well with steak seasoning and black pepper.
  2. Heat heavy pan with small amount of olive oil and brown roast well on both sides. This will take a few minutes; don’t rush the browning step.
  3. While roast browns put 1 cup beef stock in saucepan, bring to a boil and cook until reduced to 1/2 cup, then let cool slightly and mix in balsamic vinegar and tomato sauce.
  4. Peel onions and cut into thick slices. Deglaze pan with 1/4 cup water and add to sauce mixture.
  5. (You can stop at this point and refrigerate browned roast, cut onions and mixed sauce ingredients and then put them in the Crockpot when you go to work in the morning. Don’t refrigerate them in the crockery liner. Having the meat start out cold will add several hours to the cooking time, which will be good if you’re cooking it all day while you’re away.)
  6. Place onions in bottom of Crockpot. Put meat on top of onions and pour beef stock mixture over.
  7. Set Crockpot to low and cook 6-8 hours, until beef is tender. The meat might be partly submerged in liquid after this much time. (If I am home, I might turn the meat once or twice.)
  8. Remove meat from crockpot and cover with foil to keep warm.
  9. Drain liquid from Crockpot and remove as much of the fat as you can with fat separator or skimmer. Cook down liquid by about 1/3, and serve sauce with meat and onions.


I used a standard 3 1/2 quart Crockpot (affiliate link) for this recipe.

I used Szeged Steak Rub and Fini Balsamic Vinegar but there are many good brands. (affiliate links) You can use one cup from a can of beef broth for this recipe, but be sure to reduce it by simmering until it's reduced to 1/2 cup.

Nutritional information is calculated using the entire amount of balsamic vinegar and tomato sauce that goes into the slow cooker, but you're probably not eating every bit of the sauce, so actual carb counts are slightly lower.

This recipe created by Kalyn, and it's been hugely popular on the site!

Nutrition Information:



Serving Size:


Amount Per Serving: Calories: 786Total Fat: 49gSaturated Fat: 20gTrans Fat: 3gUnsaturated Fat: 26gCholesterol: 253mgSodium: 374mgCarbohydrates: 10gFiber: 1gSugar: 6gProtein: 76g

Nutrition information is automatically calculated by the Recipe Plug-In I am using. I am not a nutritionist and cannot guarantee 100% accuracy, since many variables affect those calculations.

I'd love to see your pictures if you make this recipe. Share on social media with the hashtag #kalynskitchen so I can see how it turned out for you!

Low-Carb Diet / Low-Glycemic Diet / South Beach Diet Suggestions:
With the fat trimmed well and served with the onions, this Low-Carb Balsamic and Onion Pot Roast is suitable for any phase of the South Beach Diet, and it would also be suitable for most other low-carb eating plans, which may not care about trimming the fat! Balsamic vinegar and onions both have some carbs, so concentrate on the meat and go easy on the sauce if you’re making this for a low-carb diet.

Find More Recipes Like This One:
Use the Diet Type photo index pages to find more recipes suitable for a specific eating plan. You can also Follow Kalyn’s Kitchen on Pinterest to see all the good recipes I’m sharing there. Click for Slow Cooker / Pressure Cooker Recipes on my other site!

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    172 Comments on “Low-Carb Balsamic and Onion Pot Roast (How to Make Pot Roast in a Slow Cooker)”

  1. Thanks for the super quick response, Kalyn! I plan to reduce the balsamic vinegar and add a couple tablespoons of Worcestershire and a heaping tablespoon of brown sugar. I'll come back and let you know how it worked out! Just to be safe I think I will make the potatoes on the side even though I've seen recipes with it in there – don't want to mess it up!

  2. Danielle, I don't really know how this would taste with the addition of brown sugar and Worcestershire. It's already got a lot of flavor from the balsamic vinegar, so I might reduce that a bit if you add other things.

    I'm not sure how the sauce would be with potatoes either. They would probably taste okay together, but I wouldn't cook the potatoes in the crockpot.

  3. I'm going to try to make this tomorrow! A couple questions: I've seen pot roast recipes with brown sugar and Worcestershire sauce, and it sounds a little of each in this recipe would be nice if you aren't strictly SB! My husband likes strong flavor. What do you think of those additions? Also, would red potatoes be compatible with this sauce? I know they aren't SB but my husband also happens to love meat and potatoes 🙂 Thanks, Kalyn!

  4. Erica, thanks for letting us know that worked for you.

  5. I tried it tonight with a small can of tomato paste instead of tomato sauce or diced tomatoes. It worked great! The gravy was nice and thick and I didn't have to reduce it. It was sweeter, though, so I had to add more salt. Definitely recommended though!

  6. Slow cookers are widely variable in how hot they cook (it's maddening to try to write recipes.) If there is rapid bubbling, I'd probably turn it down to low for the rest of the cooking time.

  7. Hi Kalyn,
    My crockpot has three temp settings: High, Low and Warm. Three hours into this and I am beginning to feel like my slow cook might be too fast cook. Should there be rapid bubblings alongs the edges? Reduced the liguids and it seems to have plenty left.

    Thank you,

  8. Made this yesterday for dinner. It took 15 minutes to get it in the Crock Pot and another 15 to finish it after the cook time. So easy and with such a fabulous result! Thanks for this easy recipe. Making the left-overs into a pot pie!
    Julie Trekker

  9. Linda, I don't want my recipes posted in other places like that. (People copy them from groups like that and post them on other recipe sites, which ends up hurting me in search engine results.) You're welcome to post this link to the recipe though:


    Thanks for asking and I appreciate your understanding.

  10. Kalyn, would you mind if I posted this recipe on a slow cooker yahoogroup I belong to? I'd attribute it to you of course!

  11. Linda, so glad you liked it!

  12. Dinner's over and it was dee-lish-us!! My only complaint is that there aren't enough leftovers–just one small piece of meat left. My son and his friend both loved it as well! I'll definitely be making this often and will use a bigger roast next time. Finally in the crockpot I got the 'so tender it just falls apart' meat that I hear about so often.

  13. So glad to hear you enjoyed the recipe and that you're finding the blog to be useful!

  14. I made this last weekend and it was wonderful. Had what I think ended up being unseasoned fajita meat from local farmer's market, but it worked. I will definitely make again with a roast cut of meat. Thanks for all of your wonderful SB friendly recipes. Your webite is just my favorite!

  15. Linda, sounds like you were meant to make it!

  16. This is in my crockpot now and the house smells heavenly! I've never been a balsamic vinegar fan, so I balked at buying it and looked for another recipe. Then I saw that my boyfriend had given me a bottle so I said, what the hey! Can't wait to eat it!

  17. Minda, You would probably need a bigger crockpot for a 6 pound roast. If you're adding mushrooms I'd probably keep the liquid about the same as it is here even though there is more meat. I would probably cut the mushrooms quite thick for a long cooking time like this.

    I'm afraid I'm not enough of a pressure cooker expert to give recommendations on adapting this to the pressure cooker without trying it first.

  18. This looks grand! I'd like to add mushrooms, too but my roast is 6 lbs. Should I increase the other liquids or will the liquid released from the mushrooms balance it out? Also, any tips for using a pressure cooker with this vs. a crock pot?

  19. Melissa, so glad you liked it. I think mushrooms would be a nice addition. Remember they release a lot of liquid though, so I'd reduce the other liquids.

  20. This was great!!! About an hour into cooking I thought of adding mushrooms to it. Too late but definitely next time. 😉 I dipped bites into a coarse ground mustard. Yummy!