Place a pizza stone or cast iron skillet in a cold oven and heat to 450 degrees.
Once the stone and oven is preheated, take out your stone and brush with a thin layer of olive oil or butter. I definitely prefer olive oil for this step.
Pour sourdough starter directly onto hot stone and spread into desired shape. Work somewhat quickly because the flatbread will start cooking on contact! You can do a round shape or something a little more square if you prefer.
Sprinkle with salt, garlic powder, and herbs, if desired.
Bake for 10 minutes.
Remove from oven and brush with additional butter or olive oil. Top with cheese.
Broil on low setting for 2-3 minutes or until cheese is melted/browned to your liking.
Cut into rectangles or triangles using a pizza cutter. Serve!