Prepare taco seasoning by combining all of the seasoning ingredients in a bowl or jar and mixing well.
Prep onion and bell pepper as noted and heat a large skillet over medium heat. Once hot, add in the onion, bell pepper and beef to cook, breaking the beef into bits and stirring occasionally. Cook until the beef is almost browned, about 10-12 minutes.
Preheat oven to 400° Fahrenheit.
While the beef is cooking, rice your cauliflower. Place 1/2 head of cauliflower florets in a food processor with the S-blade. Pulse to to chop into small bits, similar to a cooked quinoa or couscous consistency. Remove and add to a bowl. Repeat with remaining 1/2 of cauliflower.
Drizzle cauli rice with avocado oil. Toss to coat. Add in minced garlic and 1 tbsp of the taco seasoning. Mix and set aside.
Mix mayo (or coconut yogurt), salsa and nutritional yeast together in a bowl.
When the beef is almost browed, add in the remaining taco seasoning and mix with the meat. Continue cooking until beef is fully cooked. Remove from heat.
In a casserole dish (9x13), add the cooked beef, cauli rice, mayo mixture and olives. Stir to mix and spread everything out evenly.
Place in the oven to bake for 15 minutes, or until everything is heated through.
While the casserole is baking, prepare your toppings. When the casserole is finished, remove from the oven and top with desired items. Serve and enjoy.
1 - You can use pre-riced cauliflower, but we've found that processing fresh cauliflower this way results in a better consistency for the casserole and releases less water while cooking. 2 - Nutrition facts are an estimate provided for those following a Ketogenic or low-carb diet and do not include optional toppings for this recipe. See our full nutrition information disclosure here.