Toast bread in a toaster. With a star-shaped cookie cutter, cut out star shapes from the toast.
Peel and cut each potato into 1-inch chunks. Place potatoes in a 3-quart pot and cover with water. Cook over medium-high heat until the potatoes are almost done, adding spinach (and spinach liquid if using frozen) the last 5 to 10 minutes of cooking time. Remove pan from heat and drain, reserving cooking liquid.
Puree in batches in a blender (make sure each batch has some spinach, potatoes, and enough milk and cooking liquid to blend). Pour batches into a large pot or bowl. When finished, mix well and add salt and pepper to taste. Add more liquid if you would like a thinner soup.
Serve with sour cream or ketchup swirled into the soup with a spoo
Recipe Courtesy of Bridget Swinney