Make Ahead Mashed Potatoes

3 pounds potatoes, peeled
3/4 cup milk
1/2 cup whipping cream
1/2 cup butter
1 teaspoon salt
1/2 teaspoon pepper

Bring to boil potato chunks in salted water, then reduce heat, cover and cook for about 20 minutes until tender, then drain.
Combine milk, cream, butter, salt and pepper in a saucepan over medium-low until butter is melted. Reserve 1/4 cup of this milk mixture and place in fridge.
Add remaining milk mixture slowly to potatoes mixture until they are light and fluffy. Spray non-stick cooking spray on a 9X13 pan. Spoon in potatoes; cover and refrigerate.
Preheat oven 350° When ready to bake the next day, reheat the reserve milk mixture in the microwave. Bake covered with foil 45 minutes or until potatoes are hot. Stir before serving.