Smoked trout often gets overlooked for the more popular smoked salmon, but it’s a versatile and healthful way to get more fish in your diet. It’s meaty but flakes easily which means that although it’s tender, it won’t fall apart or mush when combined with other ingredients or heated.
Preheat the broiler. Heat 1 tablespoon vegetable oil in a large skillet over medium-high heat. Add the red onion, jalapeño, garlic and curry powder and cook, stirring occasionally, until the onion is softened, about 2 minutes. Add the tomatoes and cook, stirring, until they begin to lose their shape, 2 to 4 minutes. Remove from the heat, stir in the smoked trout and season with salt and pepper.
Arrange the bread slices on a baking sheet and brush both sides with vegetable oil (use 1 tablespoon oil per slice); season with salt and pepper. Broil the bread, turning once, until toasted, 1 to 2 minutes.
Stir half of the herbs into the trout mixture, then spoon onto the toasts. Toss the fennel with the remaining chopped herbs, 1 tablespoon vegetable oil, the fennel fronds and a pinch each of salt and pepper. Serve with the toasts.