Place the marinade from the meal kit in a bowl. Add the fish to the marinade and let marinate for 10 minutes.
Make the raita: Combine yogurt, cucumber, 2 tablespoons cilantro, and cumin together in a bowl. Taste and add salt and pepper to taste. Refrigerate until serving.
Add enough oil in a large skillet to come up ¼ inch. Heat over medium-high heat until it begins to shimmer. Fry the fish, bell pepper, and onion, and cook, stirring occasionally, for 5-6 minutes or until the fish is cooked and the vegetables are crisp-tender. Drain the oil. Add the tikka sauce from the meal kit and cook until heated through.
Serve over rice garnished with the raita on the side and cilantro leaves, if desired.