Preheat your oven to 425°F and line a baking sheet with parchment paper.
Rice the cauliflower using a food processor until it resembles fine crumbs. Steam or microwave the riced cauliflower until tender, then let it cool slightly.
Place the cooked cauliflower in a clean kitchen towel and squeeze out as much moisture as possible.
In a bowl, combine the cauliflower, egg, almond flour, and a pinch of salt and dried oregano if desired. Mix thoroughly until the mixture binds together.
Press the mixture onto the prepared baking sheet, forming a thin, even circle about 1/4 inch thick to form the crust.
Bake the crust in the preheated oven for 15-20 minutes until it begins to turn golden.
While the crust bakes, lightly grill or pan-sear the chicken breast (2 oz portion) until cooked through and set aside in thin slices.
Remove the crust from the oven and spread the marinara sauce evenly over it. Sprinkle the mozzarella cheese on top and distribute the grilled chicken slices over the cheese.
Return the pizza to the oven and bake for an additional 8-10 minutes until the cheese is melted and bubbly.
Garnish with fresh basil leaves before serving. Enjoy your protein-boosted, flavorful pizza!