Chocolate Syrup Swirl Cake

I got this recipe from http://www.HersheysSyrup.com. Try it out, I have made it several times and it is very tasty!
Ingredients
1 cup (2 sticks) butter or margarine, softened
2 cups sugar
2 teaspoons vanilla extract
3 eggs
2-3/4 cups all-purpose flour
1-1/4 teaspoons baking soda, divided
1/2 teaspoon salt
1 cup buttermilk or sour milk*
1 cup HERSHEY'S Chocolate Syrup
1 cup MOUNDS Sweetened Coconut Flakes (optional)

Instructions
1. Heat oven to 350°F. Grease and flour 12-cup fluted tube pan or 10-inch tube pan.
2. Beat butter, sugar and vanilla in large bowl until fluffy. Add eggs; beat well.
3. Stir together flour, l teaspoon baking soda and salt; add alternately with buttermilk to butter mixture, beating until well blended.
4. Measure 2 cups batter in small bowl; stir in HERSHEY'S Chocolate Syrup and remaining 1/4 teaspoon baking soda.
5. Add MOUNDS Sweetened Coconut Flakes, if desired, to remaining batter; pour into prepared pan.
6. Pour chocolate batter over vanilla batter in pan; do not mix.
7. Bake 60 to 70 minutes or until wooden pick inserted in center comes out clean. Cool 15 minutes; remove from pan to wire rack. Cool completely; glaze or frost as desired.

Serves: 20

* To sour milk: Use 1 tablespoon white vinegar plus mil to equal 1 cup.