1. Peel and chop the garlic.
2. Cut the bacon into small pieces.
3. In a pot, melt the butter and add the chopped garlic, bacon pieces, and sage leaves.
4. Sauté everything for a few minutes.
5. Peel and cut the Jerusalem artichokes into pieces.
6. Add the Jerusalem artichokes to the pot. Add enough water to cover them, season, and let cook for about 30 minutes.
7. When the vegetables are cooked, pour them into a blender and blend them with the Boursin Cuisine.