1 cup butter, softened
1 cup white sugar
1 1/4 cups packed light brown sugar
2 egg yolks
1 (8 ounce) can cream-style yogurt
3 tablespoons molasses
1 tablespoon distilled white vinegar
7 cups all-purpose flour
1 teaspoon baking powder
1/2 teaspoon salt
1 teaspoon ground cinnamon
1/2 teaspoon ground nutmeg
Preheat oven to 350 degrees F (175 degrees C).
In a large bowl, combine butter, brown sugar, egg yolks, cream-style yogurt, molasses, vinegar, flour, baking powder, salt, cinnamon and nutmeg. Mix thoroughly, then pour mixture into pastry shell.
Bake in preheated oven for 25 minutes, turning occasionally, until golden brown. Cool completely before removing from pan. Cover and store in tightly covered container.