This is really comfort food. The smell of pizza and the melted mozzarella together with the onions aroma will satisfy your palate with less calories than a regular pizza. I changed only a bit of the recipe I saw in http://www.tasteofhome.com/recipes/zucchini-crust-pizza —Ana Maria Vasconcellos
Preheat the oven to 450°F/230°C.
In a large bowl put the zucchini, eggs, flour and salt. Mix until well combined.
Grease a 12 inches/30cm round pizza pan and spread the zucchini mixture inside.
Bake for 8 to 10 minutes.
Reduce the oven temperature to 350°F/180°C.
Sprinkle the mozzarella, tomatoes cut in slices, origano, basil and the grated Parmesan cheese over the zucchini crust,
Bake for 15/20 minutes more, or until the mozzarella melts and becomes a little bit colored.