Apple Vichyssoise with Blue Cheese

1 tbsp. butter
1/3 cup chopped sweet onion (such as Maui or Vidalia)
2 cups apples, peeled and diced (Fuji apples work best), plus 1 cup finely diced apple for garnish
1/3 cup sauvignon blanc wine
2 cups chicken stock
1 cup cream
2 to 4 oz. crumbled blue cheese
Salt and pepper to taste

Melt the butter in a heavy saucepan and sweat the onions over low heat until they are clear and soft but not brown. Add the diced apples and cook until they are soft. Add the wine and chicken stock, then the cream and bring to a simmer. Add the blue cheese to taste. Check the seasoning, and add salt and pepper if desired. Puree the soup in a blender and refrigerate overnight or until well chilled. Serve chilled, topped with a garnish of finely diced apples.