Preheat oven to 400 degrees Fahrenheit. Line baking sheet with parchment paper and set aside.
In a small bowl, mix the Greek yogurt and flour to make dough. Knead dough and roll out onto prepared baking sheet to form pizza crust.
Bake crust alone for 10-12 minutes.
While crust is baking, cook taco meat. Spray skillet with non-stick spray and cook meat on medium heat. Once meat is cooked, drain any excess liquid. Add taco seasoning and water to skillet and stir to combine.
Chop tomatoes and set aside.
When pizza crust is finished baking, remove from oven.
Assemble the pizza: spread taco sauce or salsa on the pizza crust. Top with cooked taco meat, spreading out evenly. Top with cheese and bake for an additional 12-14 minutes.
When pizza is cooked, top with lettuce and tomatoes. Slice and serve!