Divide the chicken into 10 parts (2 upper and lower legs, 2 wings, 4 boneless breast pieces). Wash the chicken parts and dab dry with kitchen paper.
For the marinade, wash organic oranges hot, dry and rub the peel finely from 1. Mix the peel with oil, 1 tablespoon of oregano and 1 1⁄2 tsp. salt and pepper. Brush the chicken parts with some marinade.
Onions peel and cut into slices. Peel the grated and remaining orange (the 2nd organic orange should be left) in such a way that the white skin is completely removed. Cut the oranges into large pieces.
Wash the potatoes well and cut into quarters or halves depending on size. Peel the skin from the chorizo and cut the sausage into large pieces.
Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Mix the onions, orange pieces, potatoes and chorizo with the remaining marinade and spread in a fat pan (deep baking tray).
Put meat on top. Cook in the hot oven for 50-60 minutes. Cut the remaining organic orange into slices. Wash and dry oregano, remove the leaves. Take out the fat pan and arrange.
Garnish with orange slices and oregano.