In a large pan, heat your oil on medium and add in your leaks. Sauté for 3-4 minutes or until they break down. Stir in your garlic for 30 seconds then add in the avocados, coconut milk and salt to taste. Mix everything around and break down your avocado for about 2-3 minutes then transfer to a food processor and puree until smooth.
Salmon:
Remove the skin from your salmon pieces then slice into large cubes. Season generously with salt, onion powder, garlic powder, paprika, chili powder and oregano, then toss gently with a spoon to coat everything.
Wipe down the same pan you used for the sauce and use that. Heat your oil and then add in the salmon chunks. Cook for about 4 minutes per side or until the internal temperature reaches 145° F. Transfer to a paper towel lined platter when finished.