Fry the bacon, then add the chopped onions and sweat in a little oil. Remove and set aside.
Fry the chopped carrots and deglaze with white wine and poultry stock. Add the diced potatoes and a little sage. Simmer for about 20 minutes and then puree.
Now add the onions and bacon again and stir in the crème fraîche. Season with salt and pepper and serve garnished with sage leaves.