No more boring, bland steamed vegetables for you. This cheesy cauliflower casserole delivers the creamy richness you crave and works with either fresh or frozen cauliflower. Whether you're eating low carb or just want an easy, crowd-pleasing side dish, this simple 30-minute recipe is satisfying and surprisingly versatile.
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A reader's favorite, they keep repeating:
Sally—⭐⭐⭐⭐⭐"This is delicious and I make it a lot."
Mrs. Leeburg—⭐⭐⭐⭐⭐"This recipe is beyond delicious! It has become a staple side dish ever since we started eating low-carb, high-fat.
😊Why You'll Love This Cheesy Cauliflower Casserole
- Quick and easy: From prep to table in about 30 minutes
- Great potato lovers: It's like "cheesy potatoes" without the carbs
- Low-carb, gluten-free, and keto-friendly: without the "diet food" taste
- Versatile: using fresh or frozen cauliflower
- Easy to modify: Use a different cheese or adding flavor with your favorite spices and herbs.
- Easy to love: Perfect for family dinners or potlucks
🥣Ingredients you will need
Cauliflower (fresh or frozen)
Sour cream
Cheddar cheese (mild or sharp)
Green onions
Optional: Bacon, ham, other proteins. Smoked paprika, garlic powder
👨🍳Quick Overview: How to Make Cauliflower Casserole
1. Prep Time
a. Preheat the oven to 375° convection or 400° conventional.
b. Cook cauliflower in the microwave.
c. Slice green onions.
✅Microwave cooking cauliflower: For frozen, follow the package instructions. For fresh, wash, trim, and cook on high until tender — 4–5 minutes.
2. Mixing
Mash the cauliflower and mix with cheddar cheese, sour cream, green onion, salt, and black pepper. Bacon is optional.
3. Baking
Pour the mixture into a prepared baking pan. Cook in the oven until the top is browned and bubbling around the edges—about 20 to 25 minutes. Let it sit for 5 minutes before serving
📌For complete step-by-step instructions, scroll down to the printable recipe card or keep reading for tips, flavor options, and serving ideas.
👨🍳Add-0ns and Variations
- Cheeses: Mild cheddar, sharp cheddar, Colby Jack, or Swiss
- Spices: Garlic powder, smoked paprika, Italian herbs
- Proteins: Bacon, ham, shredded chicken
- Add some heat: cayenne pepper, hot sauce, jalapeno pepper
👍About the cauliflower
👍 Pro Tip: No matter how you cook the cauliflower, for the best texture, drain cooked cauliflower thoroughly to avoid a watery casserole.
🤔Using frozen cauliflower
This is a perfect frozen cauliflower casserole recipe. No need to thaw—just follow the package instructions to cook.
The recipe is for one pound of florets, but bags have gotten smaller. Now, most frozen cauliflower comes in 12-oz. bags. If you use 12 oz., please adjust the other ingredients accordingly.
🤔Using fresh cauliflower
You can use fresh cauliflower. One medium head of cauliflower (approximately 2 pounds) will yield about 1 pound of well-trimmed florets. You should cook the fresh cauliflower in a microwave or boil it.
To cook in the microwave: Place the cauliflower florets in a large microwave-safe bowl with a couple of tablespoons of water. Cover the bowl loosely but not tightly. Cook on high until tender, 4-5 minutes, and then drain.
⚕️Safety Tips: Fresh cauliflower should be washed to remove dirt, bacteria, and potential pesticide residue. I suggest rinsing before trimming, then a more thorough cleaning after trimming.
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😊Topping options
- No topping (my usual go-to—it’s rich enough without one)
- Low-carb topping: low-carb breadcrumbs or pork rinds, grated parmesan, crumbles of bacon, a shake of paprika (like old-fashioned scalloped potatoes)
- Higher carb toppings: cornflakes, crushed potato chips, or Ritz crackers with melted butter. Panko bread crumbs, Parmesan cheese, and melted butter can also be used.
📅Making ahead
While this is a quick and easy casserole to assemble, there may be times you need to make it ahead. Assemble the casserole, ready to cook, then prepare for storage. Refrigerate for 2 days or freeze for 2 months.
To cook, if frozen, thaw completely overnight in the refrigerator. Follow the baking instructions, but allow 5–10 extra minutes if baking straight from the fridge.
👍Related recipes to try
If you're following a low-carb diet, consider trying these popular low-carb recipes. Start with this super-easy Low Carb Tortilla Pizza and add some crunch with Low Carb Parmesan-Sesame Crackers. And top it off with Low-Carb Lemonade with Splenda.
Or try other popular cauliflower recipes, such as Garlic Mashed Cauliflower and Parmesan Roasted Cauliflower.
❄️Storage of leftovers
For leftovers, store sealed airtight in the refrigerator for up to 3 days or freeze for up to 3 months. Reheating in the microwave, but we prefer the oven.
❓FAQs
Mild cheddar is my go-to choice, but sharp cheddar offers a stronger flavor. Colby Jack, Monterey Jack, or Swiss are all great options. Use what you like and what melts well.
Nobody likes a soggy, runny casserole. Be sure to drain the cauliflower well after cooking. I always pat dry the florets with paper towels. If the cauliflower seems moist after mashing, press down on it with additional paper towels.
The other source of fluid is the sour cream. I always feel that cheaper generic sour cream is runny, so I buy the good stuff.
Lastly, a bag of frozen cauliflower is usually 12 oz., not 16 oz. anymore. If you didn't use the right amount or adjust the recipe, your casserole will be very runny.
📖The Recipe Card
Easy Cheesy Cauliflower Casserole (Fresh or Frozen Cauliflower)
Ingredients
- 1 lb frozen cauliflower
- 1 cup sour cream
- 1 cup cheddar cheese
- 3 green onions - sliced thin
- ½ teaspoon salt
- ¼ teaspoon black pepper - coarse ground
- 3 slices bacon - optional. Cooked and crumbled.
Step-by-Step Instructions
- Preheat the oven to 375° convection or 400° conventional.
- Use frozen cauliflower and cook 1 pound of cauliflower florets in the microwave. Follow the instructions on the package. Drain and pat dry.For Fresh Cauliflower: One medium head of cauliflower (approximately 2 pounds) yields about 1 pound of well-trimmed florets after trimming. Be sure to clean well.Place the fresh cauliflower florets in a large microwave-safe bowl with a couple of tablespoons of water. Cover the bowl loosely but not tightly. Cook on high until tender, 4-5 minutes, then drain and pat dry.
- Prepare a 6x9 baking dish or a 9x10 casserole dish with PAM cooking spray.
- Slice 3 green onions.
- Add the cauliflower to a large mixing bowl and mash it with a potato masher or fork. You could also use a mixer or food processor, but you are NOT trying to cream this. Add cheddar cheese, sour cream, green onion, salt, and black pepper. Bacon is optional.
- Mix well and pour the mixture into a prepared baking pan. It may be refrigerated or cooked now.
- Cook in the oven until the top is browned and bubbling around the edges—about 20 to 25 minutes. Let it sit for 5 minutes before serving.
Recipe Notes
Pro Tips
- Optional ingredients and variations are in the recipe post.
- It reheats well in the microwave, but we prefer to use the oven.
- Pan size. I usually use a 7x10 CorningWare dish. A 6x9 or an 8x8 would be good, or anything in that size range.
- Since this was initially published, many bags of frozen cauliflower have been reduced in size from 1 pound to 12 oz. The recipe will need to be decreased by 25% if that is what you have. Cooking time will be about the same.
Your Own Private Notes
To adjust the recipe size:
You can adjust the number of servings above; however, only the amount in the ingredient list is adjusted, not the instructions.
Nutrition Estimate (may vary)
I was initially inspired by my Cheesy Potatoes with Real Potatoes when we wanted a smaller, non-potato casserole side dish 15 years ago, and I've repeated the recipe many times since.
Editor's Note: Originally Published February 25, 2010. Updated with expanded options, refreshed photos, and a table of contents to help navigation.
Jan M says
This was easy and quick to prepare; I also appreciated the note provided as to the point it could be prepared ahead of time and baked later. I halved the recipe and there was still enough for 4 servings. However, I'm sorry to say we did not enjoy the taste of the sour cream at all. The extra bacon and cheese I added did nothing to cover up the sour cream taste. Some day, I may try it with yogurt as others have suggested, or cream cheese, but as is it just did not work for us.
Sally says
This is delicious and I make it a lot. I often don't have green onions so I use yellow onion or dried shallots. Easy to make variations. Sometimes we eat it as a side dish and sometimes as a main dish. Tonight I added 2 cups of leftover chili and maybe 3/4 cup of leftover corn. Added extra cheese on the top.
Marla Williams says
This looks delicious. Can it be made and frozen. If it can be frozen, then should I bake it first or just mix together to bake later?
Thank you so much.
Dan Mikesell AKA DrDan says
Hi Maria,
Welcome to the blog.
You can freeze this either before or after cooking. It should do well frozen for 2-3 months either cooked or uncooked.
If frozen before cooking, thaw completely before baking.
Dan
Dee says
Tried this last night, I added extra bacon, and it was delicious. It tasted similar to mashed potatoes. Hubby loved it and so this will be on my recipe software. Thanks!