Set oven to 325°F. Place cauliflower rice on a lightly oiled parchment-lined sheet tray. Spread out to about 1/2" thickness and roast until beginning to brown. Stir and return to the oven until all cauliflower pieces are cooked completely. Cool to room temperature.
In a bowl combine cornstarch, salt, and seasonings. Mix to evenly distribute. Set aside. In another bowl, whisk egg whites until frothy. Add cornstarch and seasonings and whisk vigorously to fully combine all ingredients and avoid any lumping. Mixture should begin to incorporate air and become light and fluffy. Fold in almond flour and parmesan.
Wrap cauliflower in a double layer of cheesecloth and wring out as much liquid as possible. Add cauliflower to egg and parmesan mixture and mix well, kneading the cauliflower into a wet "dough". Divide into equally sized dough balls of about 1 1/2 cups or 12 oz each. On a lightly oiled parchment-lined sheet tray form dough into roughly 6" rounds and refrigerate for 1-2 hours.
On a new lightly oiled parchment-lined sheet pans form discs into 10 1/2" round crusts about 3/16" thick. Bake until the crust has firmed up and become slightly crisp and golden brown on the top and bottom. Cool and refrigerate for service.
Set oven to 325°F. Place a cauliflower crust, top or crisper side down on a lightly oiled parchment-lined sheet tray.
Place 6 tomato slices equally around the perimeter of the crust about 1/2" from the edge. Sprinkle the tomatoes with 1/4 teaspoon basil and a pinch of salt. Cover with 2/3 cup cheese and bake until cheese is bubbly and beginning to brown and crust is hot and crisp.
Cut in 6 slices between the tomatoes. Drizzle with 1 tablespoon buffalo sauce. Serve hot.
If using a frozen cauliflower rice product, thaw completely and wring out the rice in cheesecloth before baking. This will shorten the baking time and a final wring out of the cauliflower will yield slightly less liquid and provide a nice crisp crust.