Serve this wonderful cake with chocolate sauce, whipped cream, ice cream, or a simple dusting of powdered sugar. I love it slightly warm with coffee!
Preheat oven to 325 degrees. Grease and flour a 10-inch tube pan (an angel food cake pan). Microwave chocolate at high for 1 minute, then 15 seconds at a time or until chocolate is melted and smooth. Beat butter with mixer for at least 2 minutes or until very creamy. Gradually add sugar beating for 5-7 minutes until light and fluffy. Add eggs, one at a time, beating just until the yellow disappears after each addition. Stir in the melted chocolate, syrup and vanilla until smooth.
Combine flour, cinnamon, soda and salt. Add to butter mixture alternately with the buttermilk, beginning and ending with the flour. Beat at low speed just until blended after each addition. Pour batter into tube pan. Bake at 325 for 1 hour and 10 minutes or until pick inserted into the center comes out clean. Cool in pan for 10-15 minutes; remove from pan and cool completely on wire rack.
*I added about 1/4 cup more flour for high altitude.
8 oz. semisweet chocolate baking squares or 60% dark chocolate chips
1 cup butter, softened
1 1/2 cup sugar
4 large eggs
1/2 cup chocolate syrup
2 tsp. vanilla extract
2 1/2 cups all-purpose flour *
1 tsp. ground cinnamon
1/4 tsp. baking soda
1 cup buttermilk