Melt one tablespoon of the butter in a saucepan over medium heat. Add the bacon and the sweet onions. Sweat gently until the onions are nice and soft. Add the white wine and the minced garlic. Reduce the white wine until almost dry. Add the chicken stock, the water and the rosemary. Season with salt and pepper and simmer for 20 minutes. Add the shelled peas and cook them until tender yet still nice and green. In the meantime, prepare an ice bath large enough to hold a stainless steel mixing bowl.
When the peas are cooked, strain most of the liquid off. Pour the peas into the bowl in the ice bath. This will stop the cooking immediately, and the peas will retain their beautiful green color. (The peas do not have to be chilled completely.)
Remove the bacon and transfer the peas to a blender, add the remaining two tablespoons of butter, and some of the cooking liquid and blend well. Pour the puree in a saucepan and adjust the thickness of the soup by adding more cooking liquid. Reheat gently, simmering for 3 to 5 minutes over low heat. Check the thickness and the seasoning again and adjust as necessary. Serve with small bread croutons and some flowering peas.
Makes 4 servings