Place cauliflower on baking sheet lined with parchment paper then spray with cooking spray and sprinkle with salt, pepper, and garlic powder. Cook in oven for 15 minutes.
While cauliflower is roasting, brown ground beef, then add taco seasoning and cook according to package instructions
Once cauliflower is done. Remove from oven and top with ground beef, cheddar cheese, and jalapenos. Return to oven and broil for 3-5 minutes.