Preheat oven to 375 degrees, Spray a large baking dish with cooking spray; set aside.
Heat 1 tablespoon olive oil in a large skillet over medium heat. Add onions, cook until the onions are tender about 5 minutes. Stir in garlic, cook until fragrant about 1 minute more.
Add ground beef, cook until brown and no longer pink about 5 minutes; drain excess fat. Stir in chili powder, cumin, and smoked paprika; season with salt and pepper. Remove from heat.
Place the peppers, cut side up, into the prepared baking dish. Drizzle each pepper with olive oil and season with salt and pepper. Spoon the meat mixture into each pepper. In a small bowl, toss together cheeses. Top each pepper with cheese.
Bake until the cheese is melted and the peppers are crisp-tender, about 20 minutes.
Top each pepper with shredded lettuce, Pico de gallo, and hot sauce if desired. Serve with lime wedges