Heat a skillet with 2 Tbsp olive oil over medium-high. Add onion; cook until translucent. Stir in beef; cook until browned. Drain fat, season with chili powder and cumin, then add tomatoes, beans, and corn. Cook 3 min, seasoning with salt and pepper
Coat a shallow baking dish with remaining oil. Layer meat and beans, top with tortillas and cheese. Repeat layers twice. Bake for 12-15 minutes or until cheese is brown and bubbly. Top with the chives and serve with your favorite toppings
