Dice the onion and sauté over medium heat for 3-4 minutes until softened.
Cut the red, green, and yellow peppers into strips, add to the pan, and cook over medium heat for 4-5 minutes.
Dice the beefsteak tomato and add to the vegetables along with the tomato paste and crème fraîche. Stir to combine.
Slice the meat sausage and add to the pan. Reduce heat to medium-low and simmer for 8-10 minutes until the sausage is cooked through (internal temperature 71°C / 160°F).