Preheat oven to 400 degrees F. Spray your casserole dish with oil of choice to prevent your meatballs from sticking.

In a small bowl, beat the egg until thoroughly combined. In a large bowl, add the ground meat, mozzarella, parmesan, beaten egg, onion powder, garlic, Italian seasoning, cayenne, and red pepper flakes. Combine this mixture with your hands until everything is evenly distributed, try not to overwork it. Using a small cookie scoop or spoon, measure out the meatballs and form them into their shapes. Place them in the casserole dish in an even layer.

Bake the meatballs in your preheated oven for 15-20 minutes, or until they are fully cooked through. By either pouring or scooping, remove the grease from the pan.

Top the meatballs with marinara sauce and cheese and place the casserole dish back into the oven for another 10 minutes, until cheese is melted and bubbly.

Top with minced basil and serve!