Wash and clean cauliflower; remove the florets from the bunch and discard the core.
Place the florets in a food processor and pulse until it is of a “rice” consistency.
In a large saucepan, heat one inch of water until it boils. Add in the cauliflower, cover with a lid, and allow to steam for 4-5 minutes. Watch closely so it does not boil over!
Preheat oven to 425° F.
Use a fine mesh strainer to drain the steamed cauliflower. Allow it to cool for a few minutes, then place in a clean dish towel (or even a paper towel) and squeeze as hard as you can to remove any excess water; add to a large mixing bowl.
Grate the mozzarella and Parmesan cheeses.
Add 1/4 cup mozzarella cheese, egg (slightly beaten), oregano, basil, and garlic salt (or garlic powder and regular salt) to the cauliflower. Stir well to combine.
Line a baking sheet with parchment paper and spray lightly with cooking spray.
Spoon the cauliflower mixture onto the pan and use your hands to form it into a 8 1/2 x 11-inch rectangle.
Bake for 30 minutes or until the crust is golden brown and firm.
Remove the crust from the oven and top with remaining mozzarella and Parmesan cheese.
Return the pan to the oven and bake for another 7-10 minutes until the cheese is melted.
Cut into “breadsticks” and serve with warm marinara sauce for dipping.