This Keto Mexican Casserole recipe is brought to you by Fiesta Brand Seasonings!
When the weather cools down, I love a good comforting casserole and this Keto Mexican Spaghetti Casserole is a new family favorite! A flavorful cheesy, rich chili tossed with roasted spaghetti squash and topped with cheese, this casserole gets devoured by everyone…even the carb lovers!

This time of year comfort food is king around here Well, while one of my favorite cold weather meals is chili, the Cowboy loves his fideo, so inspiration hit and this Keto Mexican Spaghetti Casserole was born!! It combines all the things you love, rich spicy chili tossed with low carb spaghetti squash and cheese to create the ultimate Keto Mexican Casserole!
Cooking Spaghetti Squash

Preparing spaghetti squash for this Keto Mexican Casserole is so simple, but requires a few tricks! Spaghetti squash can be difficult to cut due to how hard it is so I like to pierce it a few times with a fork or knife and microwave it for a few minutes to soften it up prior to cutting it open. The skin will be really hot, so carefully remove it from the microwave, cut both ends off, cut it in half and remove the seeds. Drizzle with avocado oil, sprinkle with salt and place cut side down on a lined sheet pan and roast at 400 degrees for 35-45 minutes or until tender.
We are going to bake the squash again, so you just want the squash to be al dente! Set aside to cool for a few minutes and then scoop the squash out of the skin to use in this Keto Mexican Casserole! You can also cook the squash ahead of time and keep it in the fridge for even faster meal prep!
Prepping this Keto Mexican Casserole could be easier!
The filling for this keto Mexican recipe is super simple! Ground beef, onions and garlic are sautéed and combined with spices like chili powder and cumin for that Mexican flare! My favorite chili powder and Mexican spices comes from Fiesta Brand Seasonings! Fiesta’s chili powder and other spices are so high quality and add great authentic Mexican flavor to any recipe! Check them out!

I don’t know about you but when I eat chili, I load it with cheese and sour cream and mix it together to get that perfect creamy, spicy chili bite. So, to get that creamy factor in this Keto Mexican Casserole, we add a little cream cheese and stir in some shredded cheddar to the chili base. The chili then gets tossed with the cooked spaghetti squash, everything goes into a casserole and into the oven till the casserole is bubbly and the cheese is melted.
Do you have a surplus of venison?
If you are a hunter or have a freezer full of venison, this recipe is a great way to use up your surplus of ground meat! If you using lean venison, make sure to add a little avocado oil or bacon drippings to the pan when browning your meat!

This Keto Mexican Casserole is a crowd pleaser for sure! Simple and easy to make, this recipe will quickly become a cold weather dinner staple! Kid and Cowboy approved!
Looking for more keto comfort food dishes? Check these out!
Keto Mexican Spaghetti Casserole
Ingredients
- 1 spaghetti squash about 3 pounds or 4 cups cooked
- 1 ½ pounds ground beef or venison
- 1/2 cup diced onion
- 1/3 cup diced bell pepper
- 1 ½ tsp. garlic powder
- 1/2 tsp. cumin
- 2 Tbsp. chili powder
- 2 Tbsp. tomato paste
- 1 cup water
- 1 ½ tsp. salt divided
- 2 oz. cream cheese softened
- 1 1/2 cups shredded medium cheddar divided
- ¼ cup sliced green onion
Instructions
To Prepare the Spaghetti Squash:
- Preheat oven to 400 degrees. Pierce the squash multiple times with a fork or knife and microwave for 3-4 minutes. Carefully remove from microwave, cut the ends off, halve the squash and scoop out the seeds. Drizzle the cut side with avocado oil, sprinkle with salt and place on a parchment lined sheet pan, cut side down. Roast for 30-45 minutes or until tender. Roast time will depend on the size of your squash.
To Prepare the Chili:
- Meanwhile, in a large skillet, cook the beef or venison over medium heat with onion, bell pepper, garlic powder and ½ tsp salt. Continue to cook until the meat begins to caramelize and the vegetables are tender. Add the chili powder and cumin and cook for an additional minute. Stir in the tomato paste, water, remaining salt and cook for 1-2 minutes or until thickened. Taste the chili mixture and adjust the salt as needed. Remove from the heat and stir in cream cheese and 1 cup shredded cheese. Stir until the cheese is melted and fully mixed in.
- Add the cooked spaghetti squash and toss to combine. Pour the chili and squash mixture into a lightly greased casserole , top with remaining cheese and bake at 400 degrees for 15 minutes or until cheese is melted and bubbly.
- Top with sliced green onions and serve warm.
Notes
Nutrition
Nutrition facts are approximate and will vary depending on the ingredients used. Carbs from sugar alcohols have been excluded since they have shown to have no impact on blood sugar.