Thinly slice the onion and soak it in water to remove bitterness. Drain well. Slice the red paprika thinly and cut the lemon into quarter wedges.

Pat the wakasagi fish dry, season with salt and pepper, and coat with flour.

In a bowl, mix lemon slices with the ★ seasonings (sugar, salt, pepper, olive oil, vinegar). Add the onion and red paprika, and mix well.

Heat olive oil in a frying pan over medium-low heat. Pan-fry the wakasagi fish until golden brown, flipping occasionally.