Prepare the salmon: Pat the salmon fillets dry with a paper towel. In a small bowl, mix together all blackening spices: paprika, chili powder, garlic powder, onion powder, cayenne, salt, and pepper. Rub the spice mix evenly over both sides of the salmon.
Cook the salmon: Heat olive oil in a skillet over medium-high heat. Add salmon fillets and cook for 3–4 minutes per side, or until blackened on the outside and cooked through. Remove from skillet and let rest for a few minutes, then flake into large chunks.
Make the sauce: In a small bowl, whisk together Greek yogurt, lime juice, honey, chili powder, and a pinch of salt. Set aside.
Warm the tortillas: Lightly toast tortillas in a dry skillet or microwave for about 15 seconds each until warm and pliable.
Assemble the tacos: Place a generous amount of shredded cabbage on each tortilla. Top with blackened salmon chunks, red onion, avocado slices, and chopped cilantro. Drizzle with the creamy sauce and a squeeze of fresh lime juice.
Serve and enjoy: Serve immediately while warm with extra lime wedges on the side.