Heat oven to 180°C. Grease tube cake pan.
In small bowl, mix all Filling ingredients; set aside.
In medium bowl, make cake batter as directed on box. Beat in sour cream.
Spread 1/3 of the batter in pan; sprinkle with 1/3 of the Filling (about 6 tablespoons). Repeat twice.
Bake about 1 hour or until toothpick inserted near center comes out clean. Cool 10 minutes; remove from pan to wire rack. Cool 10 minutes.
Meanwhile, in saucepan, heat 60 grams butter over medium heat until very light brown; remove from heat. Stir in powdered sugar and 1 teaspoon vanilla. Stir in milk, 1 tablespoon at a time, until glaze is smooth and thin enough to drizzle. Drizzle cake with glaze.