Pat the salmon fillets dry and season them with salt, pepper, and a little curry powder. Let them sit for a few minutes so the flavors absorb well into the fish. This step ensures the salmon develops a flavorful crust when seared.
Heat olive oil in a large skillet over medium heat until slightly shimmering. Place salmon skin-side down and cook until golden on both sides. Remove and set aside carefully without breaking the fillets.
In the same pan, sauté onions, garlic, and ginger until fragrant and soft. Add bell peppers, thyme, and remaining curry powder, stirring constantly. Pour in coconut milk and let it simmer until slightly thickened.
Gently place the seared salmon back into the curry sauce. Let it simmer on low heat so the fish absorbs all the rich flavors. Finish with lime juice and scallions before serving warm.