In a small bowl, whisk together the Greek yogurt, sriracha, and half the lime juice to create a spicy crema.
Toss the shredded cabbage with the remaining lime juice and chopped cilantro in a separate bowl to make the slaw.
Season the shrimp evenly with chili powder, garlic powder, sea salt, and black pepper.
Heat avocado oil in a large skillet over medium-high heat until shimmering.
Add the shrimp to the skillet and cook for 2-3 minutes per side until pink, opaque, and slightly charred.
Warm the corn tortillas in a dry pan or over an open gas flame until soft and pliable.
Assemble the tacos by layering the cabbage slaw and chili-lime shrimp into the tortillas, then finish with a drizzle of the spicy crema.