Preheat the oven to 425 degrees F.
Line a baking sheet with foil or parchment paper
In a small bowl, combine the chili powder, cumin, garlic powder, oregano, paprika, salt, and pepper.
In a medium bowl, add the sliced peppers and onion, 2 tablespoon olive oil, and half of the seasoning mixture, about 3 tsp. Mix well and then spread out onto the prepared baking sheet.
Bake in the preheated oven for 10 minutes.
Meanwhile, combine the rest of the spice mixture with the shrimp and remaining 1 tablespoon of olive oil.
After 10 minutes, add the shrimp to the baking pan and bake for another 10-12 minutes, until the shrimp and veggies are cooked through.
Serve on tortillas with cilantro, sour cream, and cheese.