In a small bowl, combine the vinegar with the crispy chili oil. Add the cucumber, stir, and let sit while you make the fish.
Combine the batter mix from the kit with 10 tablespoons of water. Whisk until smooth. Place the seasoned flour from the kit on a plate or in a shallow bowl. Coat the fish in batter then dredge in the seasoned flour.
Add enough oil in a large skillet to come up ¼ inch. Heat over medium-high heat until it begins to shimmer. Fry for 3-4 minutes per side or until golden brown. Toss with the Korean Chili Sauce from the kit and serve over rice. Top with cilantro and serve spicy cucumber salad on the side.