Preheat oven to 500 degrees.
Spread desired amount of hummus on each piece of pita bread.
Top with onion, cherry tomatoes and red pepper flakes.
If making the pesto pizza, add pesto and walnuts to the base ingredients.
If making the spicy pizza, add jalapeños to the base ingredients.
Place pitas on a baking sheet and bake for 10-15 minutes or until bread is crispy. Remove from the oven.
If making the pesto pizza, top cooked pizza with fresh basil.
If making the spicy pizza, top cooked pizza with cilantro.
Slice, serve and eat.