Marinate the shrimp: In a medium bowl, toss shrimp together with garlic powder, onion powder, chili powder, chipotle in adobo liquid, brown sugar or honey and lime juice until evenly coated. Let shrimp marinate while preparing slaw and sauce.
Prep the avocado sauce: Place the greek yogurt, avocado, lime juice, garlic clove, cilantro, salt and a few turns of cracked black pepper into a food processor. Blend on high until the sauce is smooth and fluffy. If the sauce is too thick, thin it out with 1 teaspoon of water at a time until dressing consistency is reached. Adjust seasoning to taste.
Divide half the sauce over the slaw mixture and stir together. Save the other half for topping on tacos.
In a medium pan, heat the olive oil on medium heat. Add in shrimp and marinade contents. Cook for 5-6 minutes, or until shrimp are pink and opaque in the center.
Char corn tortillas on an open gas flame or in a dry skillet.
Pile slaw, a few pieces of shrimp, avocado slices and extra sauce into corn tortilla. Top with a small crumble of cotija cheese and Sriracha, if using.