We love a recipe with a special meaning, and this special Thanksgiving side dish is close to Mary Berg's heart. Whip up her mom, Myra Berg's mashed potato casserole is the perfect make-ahead dish.
TIP: You can prepare this casserole up to three days in advance. Cover the unbaked casserole with plastic wrap and store it in the fridge. Add 15 to 20 minutes to ensure the centre is warm to bake.