11. Heat oven to 350°F. Grease bottom and side of 10-inch angel food (tube) cake pan with shortening; lightly flour.
2. In small bowl, mix all Blackberry Filling ingredients; set aside.
3. In medium bowl, sift together flour, baking powder and baking soda; set aside. In large bowl, beat granulated sugar, butter, vanilla and eggs with electric mixer on medium speed 2 minutes, scraping bowl occasionally. Beat in flour mixture alternately with sour cream on low speed.
4. Spread one-third of the batter in pan; sprinkle with half of the filling. Spoon another one-third of the batter by tablespoonfuls over filling; sprinkle with remaining filling. Spoon remaining batter over filling; spread evenly.
5. Bake coffee cake 55 to 65 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes; remove from pan to wire rack. Cool completely, about 1 hour 30 minutes.
6. Meanwhile, in small bowl, stir all Powdered Sugar Glaze ingredients until smooth and thin enough to drizzle. Drizzle over cooled coffee cake.