Preheat your oven to 400°F and line a baking tray with parchment paper.
Break the cauliflower into florets and pulse in a food processor until it resembles rice. Transfer the riced cauliflower to a microwave-safe bowl and microwave on high for 4-5 minutes until softened. Let it cool slightly.
Once cooled, place the cauliflower in a clean towel and squeeze out as much moisture as possible.
In a bowl, combine the drained cauliflower, egg, and grated Parmesan cheese. Mix well until the mixture binds together.
Transfer the mixture onto the prepared baking tray and press it into a thin, even circle to form the crust. Score lightly around the edges if desired.
Bake the crust in the preheated oven for about 20 minutes or until the edges begin to turn golden and crisp.
Remove the crust from the oven and spread the tomato sauce evenly over the top. Sprinkle the fresh mozzarella evenly and distribute the basil leaves over the cheese.
Return the pizza to the oven and bake for an additional 5-7 minutes until the cheese has melted and is slightly bubbly.
Remove from the oven, let it cool for a few minutes, slice, and enjoy your wholesome, crispy cauliflower crust pizza.