Place cauliflower in a food processor and blend until it reaches a fine consistency. In a bowl combine cauliflower, egg white protein, and water. Mix together until well combined. Place mixture on a parchment paper lined baking sheet and spread into a circle. Make sure the circle is not too thin as it will stick to the parchment paper. Bake for 40 minutes at 400 degrees. Remove from oven and flip crust onto a plate to remove the parchment paper. Top with desired toppings. Place back in the oven (on a new sheet of parchment paper) to cook toppings and melt cheese.