1. Heat oil in a large nonstick skillet over medium- high heat. Add fish chunks, season with salt and pepper, and cook, stirring often but carefully, until pieces are cooked through, about 3 minutes. Transfer to a bowl with a slotted spoon and set aside.
2. Add onion, bell pepper, and jalapeno pepper to skillet and cook over medium-high heat until somewhat softened, about 5 minutes. Return fish to skillet, sprinkle with chili powder and cumin, and cook, stirring often, just until heated through.
3. Remove from the heat. Squeeze lime juice over the fish. Top with the cilantro.
4. To serve, spoon the fish mixture into the lettuce leaves and fold over taco-style.
M1 Caution Modification: Add sour cream or tartar sauce.
280 calories per serving