Gather all the ingredients. Preheat the oven to 400°F. Cut a piece of cooking aluminum foil to approx 32 inches long by 12 inches wide. Place on top of a regular cookie sheet with half of it extended beyond the sheet.
Prepare all the ingredients and put all the sausages, vegetables, seasonings and oil (except the garnish) on the foil on the sheet. Fold the foil over the ingredients and secure the three open sides of the foil by rolling the edges on itself. Wrap the foil loosely so that there is space for the food to steam inside the packet.
Pop the the cookie sheet with the papillote in the preheated oven for one hour.
Remove from the oven and let rest for 10 minutes. Carefully open the foil; the food should be steaming hot inside. Place the entire packet on a pretty serving platter, sprinkle with garnish and serve immediately. Bon appétit!