Chicken Casserole with leek

1 tablespoon butter 1 tablespoon olive oil 1 leek , sliced 1 small onion , chopped 2 -3 garlic cloves , crushed 2 skinless chicken breasts , cut into 2cm[...]

2 tablespoons olive oil 8 chicken thighs , on the bone 1 red pepper, seeded and quartered 1 green pepper , seeded and quartered 2 garlic cloves , finely[...]