Preheat the oven (or air fryer) to 180°C.
Whisk the eggs in a medium mixing bowl.
Add the sardines and mash lightly with a fork - you want a slightly chunky texture.
Stir in the soy sauce, mirin, sesame oil (if used) and rice vinegar.
Sift in the chickpea flour and mix until smooth.
Fold in the edamame beans and chopped spring onions.
Divide the mixture between two deep muffin moulds or ramekins (or make smaller portions for snacks).
Bake or air fry for about 15 minutes, until golden and set.
Serve warm or cold with a salad, steamed vegetables, drizzled with soy sauce.