Vegetable croquettes with chicken

INGREDIENTS
200 g chicken fillets
200 g frozen peas
200 g corn kernels
60 g flour
50 g grated Emmental cheese
40 g butter
4 egg yolks
2 carrots
1 chicken stock cube
25 cl milk
3 tbsp. ketchup
2 tbsp. olive oil
fine breadcrumbs
salt

PREPARATION
Cut the chicken fillet in half and poach it for 10 minutes in a pan of boiling water with the stock cube. Drain it, then blend it.
Peel the carrots and cut them into small cubes. Cook them for 5 minutes in a pan of boiling salted water with the peas. Drain them carefully, pressing them with your hands to remove as much water as possible. Rinse and drain the corn.
Mix the vegetables and chicken in a bowl.
Melt the butter in a small pan over a low heat, add the flour all at once and mix well. Pour in the milk a little at a time to obtain a lump-free béchamel sauce, season with salt and pepper and cook for 2 minutes without stopping to stir.
Remove from the heat, add the egg yolks, grated Emmental cheese and ketchup. Pour this mixture into the bowl, mix well and leave to cool for 1 hour in the refrigerator.
Shape 16 croquettes of 6 cm diameter by hand or with a cookie cutter, sprinkle with breadcrumbs. Cook for 3 minutes on each side in a non-stick pan with 1 tablespoon of olive oil. Serve immediately with ketchup.