Preheat oven to (450°F – 230°C) and set the oven rack to the middle position.
Lined a pizza baking pan with parchment paper. If you don’t have parchment paper, spray some pan release onto the baking tray.
Wash the cauliflower thoroughly then remove the buds from the cauliflower and cut them into small pieces.
Place the cauliflower pieces into the food processor and pulse for a few seconds until it has a rice texture.
If you don’t have a food processor, you can cut the cauliflower very thin or you can use a cheese grater.
Place the riced cauliflower into a strainer and squeeze out as much water as possible.
In a medium-size bowl, add the riced cauliflower, egg, garlic, salt, basil, sage, and 1/2 cup of mozzarella and stir until a dough is formed.
Gently work the cauliflower dough with your fingers spreading the dough outward into a round shape of a pizza crust about 1/4 inch thickness.
Place the baking pan into the oven and bake for about 12-15 minutes until the cauliflower crust is light golden brown.
Remove the crust from the oven and slightly cool for about 5 minutes.
Topping: Add the sauce onto the pizza crust followed by the mozzarella cheese, plum tomatoes, onions, green peppers and put back in the oven and bake for about 5-8 minutes or until the cheese is completely melted.
Remove from oven and serve.