Old Fashioned Sweet Potato Pie

Name: Old Fashioned Sweet Potato Pie
Prep time: 10 min
Cook time: 45 min
Total time: 55 min
Cuisine: American
Ingredients: 2 cups peeled cooked sweet potatoes; 1 1/4 cups sugar; 1/4 cup melted butter; 2 eggs; 1 teaspoon vanilla extract or 1 -2 tablespoon Bourbon; 1/4 teaspoon salt; 1/4 teaspoon ground cinnamon; 1/4 teaspoon ground ginger; 1 cup milk; 1 (9 inch) unbaked pie shells; 3 egg whites