Cream of Asparagus Soup
8 tablespoons( 1 stick) unsalted butter
4 cups chopped yellow onions(about 4 large onions)
2 quarts chicken stock, thoroughly defatted
2 pounds asparagus
Salt and freshly ground black pepper, to taste
½ cup heavy cream or buttermilk(for cold soup)
1. Melt the butter in a large pot over low heat and simmer the onions until very soft and golden, stirring often, about 25 minutes.
2. Add the chicken stock and bring to a boil.
3. Meanwhile, trim the tips from the asparagus and reserve. Cut about 1 inch from the butt ends of the asparagus spears; don't try to remove all of the tough parts, just the very woody ends. Chop the spears into ½ inch pieces and drop into the boiling chicken stock, cover, reduce heat, and simmer until the asparagus is very soft, 45 minutes.
4. Force the soup, broth and all, through the medium disc of a food mill. Return the puree to the pot, add the reserved asparagus tips, and simmer until they are tender but still firm, 5 to 10 minutes. If serving the soup hot, season with salt and pepper and serve.
5. If serving the soup cold, remove from the heat, cool, stir in the cream or buttermilk, and refrigerate, covered. Season with salt and pepper. Serve very cold.