Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper.
In a small bowl, mix together the Cajun seasoning, garlic powder, onion powder, smoked paprika, salt, and black pepper.
Place the salmon fillets on the prepared baking sheet and drizzle with olive oil. Rub the spice mixture evenly over the salmon fillets.
Bake the salmon in the preheated oven for 12-15 minutes, or until the salmon flakes easily with a fork.
While the salmon is baking, prepare the creamy avocado lime sauce. In a medium bowl, mash the avocado with a fork until smooth.
Add the Greek yogurt, lime juice, minced garlic, salt, black pepper, and cilantro (if using) to the mashed avocado. Mix until well combined and creamy.
Once the salmon is done, remove it from the oven and let it rest for a few minutes. Serve the salmon topped with the creamy avocado lime sauce.