Heat the oven to 400°F (200°C). Brush both sides of the tortillas lightly with oil and arrange them on two baking sheets.
Bake for 5 minutes, flip, and bake 3–5 minutes more until crisp and lightly golden.
Meanwhile, warm the beans with the cumin, chili powder, garlic powder and salt in a saucepan. Mash them, adding a few spoonfuls of the reserved liquid until spreadable.
Spread the beans over the crisp tortillas and sprinkle with cheese. Return to the oven for 3–4 minutes until the cheese melts.
Top with lettuce, salsa, avocado and cilantro, and serve with lime wedges and yogurt.