Preheat oven to 400 degrees.
In a food processor, or blender, combine all ingredients for pesto. Puree until smooth. If too thick, add more oil or lemon juice. If too thin, add more basil, pine nuts, or nutritional yeast. Taste and season with salt and pepper according to your preferences.
Spread flatbreads with pesto, and layer toppings: cheese, tomato, onion, and green olives. Place on a baking sheet and bake for about 10 to 15 minutes or until cheese is melted and veggies are slightly tender.
When ready to serve, add a small drizzle of balsamic glaze on top.