Heat oven to 350°F. Grease 12-cup fluted tube cake pan or 10-inch angel food (tube) cake pan.
To toast pecans: lay a single layer of pecans on a baking sheet. Place into preheated oven. allow to toast slightly, stirring every 10 minutes or so, until browned slightly. Allow to cool completely before chopping.
In a small bowl, mix all Filling ingredients; set aside.
In a medium bowl, mix flour, baking powder, baking soda, and salt; set aside. In a large bowl, beat granulated sugar, 3/4 cup butter, 1 1/2 teaspoons vanilla, and the eggs with electric mixer on medium speed 2 minutes, scraping bowl occasionally. Beat in flour mixture alternately with sour cream on low speed.
Spread 1/3 of the batter (about 2 cups) in pan; sprinkle with 1/3 of the Filling (about 6 tablespoons). Repeat twice.
Bake about 1 hour or until a toothpick inserted near the center comes out clean. Cool 10 minutes; remove from pan to wire rack. Cool 10 minutes.
Meanwhile, in a 1 1/2-quart saucepan, heat 1/4 cup 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.