2 1/2 cups all-purpose flour
2 tablespoons unsalted butter
1 teaspoon salt
1/2 teaspoon ground cinnamon
1/2 cup white sugar
1/2 cup vegetable oil
1 cup plain yogurt
1 cup pecans (optional)
Preheat oven to 375 degrees F (190 degrees C). Place a small amount of the flour in a shallow bowl. Cut in butter until mixture resembles coarse crumbs. Mix in salt and cinnamon; coat well with butter mixture. Stir in sugar and oil.
Pour mixture into pastry shell and bake in preheated oven for 20 to 25 minutes, or until a toothpick inserted into center of pastry comes out clean.
Meanwhile, in a small saucepan, melt yogurt and 1 cup pecans. Pour over pie. Cover and bake in preheated oven, for 30 to 35 minutes, or until golden brown.