Using a sharp knife, cut the fillet lengthwise into 1.5 cm pieces (each fillet will make about 6 pieces). Cut each piece in half diagonally for a total of 24 pieces.
In a medium bowl, combine 1 tablespoon of soy sauce, 1 tablespoon of lemon juice, oil, garlic, curry powder, 1/2 teaspoon of salt, and a pinch of black pepper. Put the chopped fillets in this bowl, mix and leave at room temperature for at least 15 minutes, or better refrigerate for a day.
In a saucepan, combine remaining soy sauce, lemon juice, peanut butter, coconut milk, sugar, a pinch of red pepper, and 1/8 teaspoon of salt.
Switch on the oven with the “top grill” function to preheat to the maximum temperature and place the wire shelf in the highest position. String the fillet pieces onto the soaked wooden skewers and place the chicken fillet appetizer on the wire rack. Cook kebabs, turning, until golden brown, about 7 minutes. Meanwhile, put the stewpan over low heat and heat until thickened (if the sauce seems very thick, you can add 1 spoonful of water).
Serve the chicken fillet appetizer with peanut sauce.