In a medium bowl, combine the yeast, sugar, and warm water. Mix well and let it sit in a warm place for 5 to 7 minutes until it becomes foamy.
In a large mixing bowl, whisk the sorghum flour, brown rice flour, cornstarch, xanthan gum, and salt together.
Pour the yeast mixture into the bowl with the flour mixture and add the vegetable oil, stirring with a wooden spoon until you get a homogenous, shaggy, wet dough.
Spread the dough into a greased round pizza pan and let it rise for 30 minutes in a warm place.
Meanwhile, cut the zucchini into quarters lengthwise and then slice. Toss the vegetables with salt in a medium bowl and then place the pieces on top of paper towels in a single layer to let excess water drain.
Mince the garlic, and thinly slice the onions. Mince the chives, if you are using them.
Meanwhile, sauté the onions on low heat in a large skillet with a little oil until they are caramelized. Add the minced garlic and sauté until fragrant, stirring constantly for about 30 seconds.
Preheat the oven to 350°F and then pre-bake the dough for 30 minutes.
Place the sliced cheese in one layer on top of the pre-cooked crust, top with caramelized onions and garlic, and finally top with zucchini. Bake for another 10 to 20 minutes until the cheese is melted before topping with fresh chives and slicing into pieces.