For the Shishito Pepper Salsa
Add 1 tbsp of vegetable oil to a large cast iron on medium-high heat. Add shishito peppers in batches, turning over often.
Once slightly charred, place on a cutting board to cool and then chop.
Add the garlic, vinegar, salt and pepper to a bowl and stir in the peppers. Set aside.
For Baked Chicken Tacos Al Pastor
Preheat oven to 400 °F. Spray a 9 x 13 casserole dish with non-stick cooking spray.
Preheat a large skillet to medium-high heat. Add the olive oil, ground chicken, onion, garlic, salt and pepper. Cook chicken until no longer pink − about five minutes.
Add chipotle powder, cumin, coriander, pineapple juice, and water. Bring to a boil and then turn heat down to low, stirring occasionally. When sauce has thickened, drain the liquid from the skillet.
In the prepared baking dish, place the hard shell tacos. Fill shells with taco meat and top with cheese.
Bake in oven until cheese melts, about 5 minutes.
Remove the casserole dish from the oven and garnish each taco with avocado slices, fresh cilantro, and shishito pepper salsa.