- 3 cups all-purpose flour
- 1/4 teaspoon salt
- 1/4 teaspoon baking soda
- 1 1/2 cups butter, softened
- 3 cups white sugar
- 6 eggs
- 1 cup sour cream
- 1 teaspoon vanilla extract
- 1 (7 ounce) package sweetened flaked coconut
- 1 cup milk
- 2 tablespoons cornstarch
- 1 cup white sugar
- 1/2 cup butter, softened
- 1/2 cup solid vegetable shortening
- 2 teaspoons vanilla extract
- 1/2 (7 ounce) package sweetened flaked coconut
- Preheat oven to 300 degrees F (150 degrees C).
- Grease a 10-inch tube pan.
- Combine flour, salt, and baking soda in a bowl.
- Beat 1 1/2 cup butter and 3 cups sugar with an electric mixer in a large bowl until light and fluffy. The mixture should be noticeably lighter in color.
- Beat eggs one at a time into butter mixture, allowing each egg to blend completely before adding the next. Beat in sour cream and 1 teaspoon vanilla extract with the last egg.
- Gradually stir flour mixture into egg mixture, mixing until just incorporated.
- Fold in 7 ounces flaked coconut, mixing just enough to evenly combine. Pour the batter into prepared pan.
- Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 90 minutes. Cool in the pan for 10 minutes before removing to cool completely on a wire rack.
- Whisk milk and cornstarch in a saucepan over medium heat until mixture becomes very thick, stirring constantly, about 5 minutes; set aside to cool completely.
- Beat 1 cup sugar, 1/2 cup butter, and shortening with an electric mixer in a bowl until mixture is smooth and creamy.
- Beat cooled milk paste and 2 teaspoons vanilla extract into sugar mixture to achieve a light and creamy frosting.
- Spread frosting over completely cooled cake and sprinkle remaining 3 1/2 ounces flaked coconut over the frosting.