Cauliflower Rice Sausage Casserole won’t win any beauty contests, but this is amazingly delicious for an easy low-carb and Keto dinner! And if you haven’t tried a casserole with cauliflower rice, I think you’re going to be surprised how comforting it is!

Pin Cauliflower Rice Sausage Casserole to try it later!

Cauliflower Rice Sausage Casserole close-up photo

If you’re a regular reader, you’ve probably noticed how I’m a fan of low-carb and Keto casseroles! Mostly I think it’s the way you can make a casserole on the weekend and it guarantees leftovers for a few days. (At least that’s true for me; if you have a house full of teenage boys that probably isn’t going to work.)

This new recipe for Cauliflower Rice Sausage Casserole was inspired by Brown Rice Casserole with Sausage and Peppers that’s back in the archives of the blog. I love that old recipe and used to make it often back in the days when I followed South Beach and ate brown rice more often.

But now most of my regular readers probably would prefer a version with cauliflower rice, and when I read through the recipe I was pretty sure that switch would work! I used frozen cauliflower rice to make it extra easy to get this on the table, and added some mushrooms to the original recipe, which was a nice bonus.

And after I tested this recipe with Kara and had some leftover in the fridge, I noticed how much I enjoyed it every time I pulled one out. And when I talked to Kara later about how she enjoyed her share of the leftovers, we both agreed it might have been even better when it was reheated, FTW! I didn’t manage to freeze any, but I’m sure this would freeze well. And I hope you try it; this is absolutely a winner!

What ingredients do you need?

(This is only a list of ingredients; please scroll down for complete printable recipe. Or if you use the JUMP TO RECIPE link at the top of the page, it will take you directly to the complete recipe.)

  • frozen cauliflower rice
  • Olive Oil (affiliate link)
  • Italian Sausage, turkey or pork 
  • mushrooms
  • onion
  • green pepper
  • Italian Herb Seasoning (affiliate link)
  • ground fennel (affiliate link)
  • salt and fresh-ground black pepper to taste
  • grated Mozzarella cheese
  • green onions to garnish (optional)

What sausage did we use for the Califlower Rice Sausage Casserole?

I would love this recipe with my favorite turkey Italian sausage. But lately that has been hard to find, and mild or spicy pork Italian sausage will also be delicious.

What kind of mushrooms did we use?

We used brown Cremini mushrooms for this recipe, but if you prefer white mushrooms they will also be fine.

Want more low-carb dinner ideas with Italian Sausage?

Check out 40 Low-Carb and Keto Italian Sausage Recipes for more tasty dinners with Italian Sausage.

Cauliflower Rice Sausage Casserole process shots collage

How to Make Cauliflower Rice Sausage Casserole:

(This is only a summary of the steps for the recipe; please scroll down for complete printable recipe. Or if you use the JUMP TO RECIPE link at the top of the page, it will take you directly to the complete recipe.)

  1. Preheat oven to 375F/190C and spray dish with nonstick spray. 
  2. Take cauliflower rice out of the freezer and let it start to thaw.
  3. Chop mushrooms, onion, and green bell pepper and slice green onions.
  4. Heat oil and cook sausage over medium-high heat until it’s nicely browned. 
  5. Remove sausage, add more oil, add chopped mushrooms, and cook until mushrooms have released their liquid and liquid has evaporated. Remove mushrooms.
  6. Heat another 2 tsp. oil; then add onions and green pepper and cook until they are starting to brown. Add spices and cook 2 minutes more.
  7. Add cauliflower rice to the pan and heat for few minutes. Season with salt and fresh-ground black pepper.
  8. Add cooked sausage and mushrooms and gently combine with other ingredients.
  9. Then add 1 cup grated mozzarella and stir to distribute the cheese.
  10. Put mixture into the casserole dish and sprinkle the other cup of cheese over the top.
  11. Bake about 25 minutes, or until the top is starting to lightly brown.
  12. Serve hot, garnished with diagonally-sliced green onions if desired.

Cauliflower Rice Sausage Casserole in baking dish

Make it a Low-Carb Meal:

This would be delicious with Spinach Salad with Bacon and Feta or Kalyn’s Favorite Baby Arugula Salad served as a side dish.

More Low-Carb and Keto Casseroles with Cauliflower:

Cauliflower Rice Sausage Casserole close-up photo
Yield: 6 servings

Cauliflower Rice Sausage Casserole

Prep Time 20 minutes
Cook Time 25 minutes
Total Time 45 minutes

Cauliflower Rice Sausage Casserole was inspired by an Easy Brown Rice Casserole with Italian Sausage and Bell Pepper that's back in the archives of the blog.

Ingredients

  • 1 10 oz pkg. frozen cauliflower rice (see notes)
  • 5 tsp. olive oil, divided
  • one 19.5 oz. pkg. uncooked Italian Sausage (see notes)
  • 1 lb. mushrooms, chopped
  • 1 small onion, chopped
  • 1 green pepper, chopped
  • 1 tsp. Italian Herb Blend
  • 1/2 tsp. ground fennel (see notes)
  • salt and fresh-ground black pepper to taste
  • 2 cup grated Mozzarella cheese
  • 3 green onions to garnish (optional)

Instructions

  1. Preheat oven to 375F/190C and spray a casserole dish with nonstick spray. (I used a dish that was 8" x 11" but any size close to that will work.)
  2. Take the cauliflower rice out of the freezer and let it thaw while you start the recipe.
  3. Chop mushrooms, onion, and green bell pepper and slice green onions.
  4. Heat 2 tsp. oil in a large non-stick frying pan and cook sausage over medium-high heat until it's nicely browned. We use a potato masher (affiliate link) to break the meat apart as it cooks.
  5. Remove sausage to a bowl, add another teaspoon of oil, add chopped mushrooms, and cook until mushrooms have released their liquid and all liquid has evaporated. Transfer mushrooms to the bowl with the sausage.
  6. Heat another 2 tsp. oil in the frying pan; then add onions and green pepper and cook until they are barely starting to brown. (You need this much oil for the cauliflower rice, which will be added next.)
  7. Add spices and cook 2 minutes more.
  8. Add cauliflower rice to the pan with onions and peppers and heat for a couple of minutes. Season with salt and fresh-ground black pepper to taste.
  9. Add the cooked sausage and mushrooms to the pan and gently combine with other ingredients. Then add 1 cup grated mozzarella and stir to distribute the cheese in the mixture.
  10. Put the mixture into the casserole dish and sprinkle the other cup of cheese over the top.
  11. Bake about 25 minutes, or until the top is starting to lightly brown.
  12. Serve hot, garnished with diagonally-sliced green onions if desired.

Notes

A ten-ounce package of frozen cauliflower rice is 2 1/2 cups; if you're taking the cauliflower rice from a larger package I might increase to 3 cups, or even slightly more.

I used my favorite spicy turkey Italian Sausage, but use pork sausage if you prefer more fat. Ground Fennel (affiliate link) is optional, but highly recommended!

Use full-fat or reduced-fat Mozzarella, whichever you prefer.

Cauliflower Rice Sausage Casserole was inspired by an Easy Brown Rice Casserole with Italian Sausage and Bell Pepper that's back in the archives of the blog.

Nutrition Information:

Yield:

6

Serving Size:

1

Amount Per Serving: Calories: 506Total Fat: 38gSaturated Fat: 15gUnsaturated Fat: 23.1gCholesterol: 82mgSodium: 1032mgCarbohydrates: 8.5gFiber: 3.2gSugar: 5.9gProtein: 29g

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.

Did you make this recipe?

Did you make this recipe? Please leave a star rating (under the PRINT button in the recipe) or share a photo of your results on Instagram! THANKS!

Square image for Cauliflower Rice Sausage Casserole shown in baking dish.

Low-Carb Diet / Low-Glycemic Diet / South Beach Diet Suggestions:
If you use full-fat mozzarella this Cauliflower Rice Sausage Casserole it’s a great dish for low-carb diet or Keto plans. You can also use pork Italian Sausage for Keto if you prefer, but I would reduce the amount of oil when cooking the sausage. If you want to make this work for the original South Beach Diet, be sure to use turkey Italian Sausage and low-fat mozzarella, and maybe reduce the amount of cheese.

Find More Recipes Like This One:
Use Casseroles for more recipes likes this one. Use the Diet Type Index to find recipes suitable for a specific eating plan. You might also like to follow Kalyn’s Kitchen on Pinterest, on Facebook, on Instagram, on TikTok, or on YouTube to see all the good recipes I’m sharing there.

Historical Notes for this Recipe:
Cauliflower Rice Sausage casserole was first posted in 2020 and was adapted from an earlier casserole recipe that used brown rice. It was last updated with more information in 2023.

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