Preheat oven to 350°. Reheat Potato Cakes according to recipe instructions on page 105.
Add water to a depth of 2 inches in a large nonstick skillet. Add vinegar. Bring to a boil; reduce heat, and maintain at a light simmer. Break eggs, 1 at a time, into a measuring cup or saucer; slip eggs, 1 at a time, into water, holding cup as close as possible to surface of water. Simmer 5 minutes or until done. Remove eggs with a slotted spoon.
Combine sauce mix and milk in a small saucepan; stir with a whisk until smooth. Add butter. Bring to a simmer over medium heat, stirring constantly with a whisk, 2 minutes or until thickened; stir in tomato sprinkles.
Place potato cakes on plates; top with eggs. Spoon sauce over eggs.