For the chipa with chicken filling, cook the chicken breast in a little water (or chicken soup).
Meanwhile, sauté the finely diced bell bell pepper and onion in the oil. Finally, add the finely diced tomatoes and continue to simmer at a low temperature until a uniform creamy consistency is reached.
Add a pinch of sugar as a flavor enhancer. Finally, stir in the very finely diced chicken and season strongly with salt and freshly ground pepper. Heat everything again, then remove from heat and let cool.
In a bowl, mix flour, cornstarch, grated cheese and salt well and make a well. Add egg, softened butter and a little milk to the well. Knead until a silky dough is formed. If necessary, add a little more milk.
The dough should be compact.
Form small balls from about 100 g of dough each. Press a hole in the balls so that about 1 tablespoon of the filling fits inside. After filling, squeeze well. Place the chipa not too close to each other on a baking tray and bake at 220 °C for about 20 minutes until golden. Check them from time to time.
Serve the chipa with chicken filling while still warm.