Grease a 10-inch fluted tube pan. Sprinkle with 3 teaspoons sugar; set aside. In a large mixing bowl, cream butter and remaining sugar until light and fluffy, about 5 minutes. Add eggs, one at a time, beating well after each addition. Stir in bananas and extracts. Combine flour and baking soda; add to the creamed mixture alternately with sour cream, beating just until combined.
Pour into prepared pan (pan will be full). Bake at 325 degrees for 75–85 minutes or until a toothpick inserted near the center comes out clean. Cool for 10 minutes before removing from pan to a wire rack to cool completely.
In a small bowl, whisk glaze ingredients until smooth; drizzle over cake. Store in refrigerator. May freeze for up to 1 month.