Remove broad beans from their pods, make a small cut in the skin, and peel off the thin skin. Thinly slice the onion.

In a bowl, combine the broad beans, onion, and sakura shrimp. Sprinkle 1 tbsp of all-purpose flour over the mixture and coat evenly.

In a separate bowl, mix the batter ingredients (4 tbsp all-purpose flour, 2 tbsp potato starch, and 5 tbsp cold water). Add the coated vegetables and gently mix.