Combine all spices together in a small bowl. Pat the salmon dry with paper towels and sprinkle the spice mix evenly over both sides of the fish.
Preheat a cast iron (or nonstick) skillet for several minutes over medium-high heat. Add oil and let it preheat for 30 seconds before addinmg the salmon (skin-side-down if it has skin). Cook undisturbed until it releases easily from the pan, about 4 minutes.
Flip the salmon and add the butter to the pan. Once melted, tilt the pan and spoon the butter over the salmon for 1-2 minutes until salmon is cooked through (it should reach 125ºF for perfectly moist fish; if you don’t have a thermometer, test with a knife - it will flake easily and be opaque when done). Transfer salmon to a plate to rest for a few minutes.
Add the honey to the pan with a pinch of salt and chili flakes; simmer until slightly thickened and glossy, less than a minute. Spoon the sauce over the salmon and serve.
Video
Notes
You can swap 2 tbsp cajun seasoning for the spice blend if you have it on hand.
Preheating the pan and then the oil are the keys to ensuring your fish doesn’t stick.