1. Preheat oven to 450F/230C. In a small bowl, mix Cajun seasoning with salt.
2. Line a baking sheet with aluminum foil, and place the salmon on top (skin side down if your fillets still have the skin on). Spread a layer of yogurt on top of each fillet, and sprinkle the top with the seasoning mixture.
3. Roast uncovered in the oven for about 15-20 mins, depending on the thickness of your fish. Slide a spatula or flipper under the fillets and serve them on plates with lime slice on top. (If they still have the skins on, you should be able to separate the flesh from the skin with the flipper as you take it off of the foil.)