Add the chopped toasted pecans, brown sugar, and cinnamon to a medium bowl. Mix well in set aside.

Preheat oven to 325 degrees F.

Grease and flour a 12-cup bundt pan. Set aside until needed.

Add the flour, baking soda, and salt into a large bowl. Whisk to combine, then sift the mixture. Set aside until needed.

Add the butter and granulated sugar to the bowl of a stand mixer fitted with the paddle attachment and beat on high speed until light and fluffy (3-4 minutes). Scrape the sides and bottom of the bowl as needed.

Add the eggs one at a time to the mixer on medium speed. Scrape the sides and bottom of the bowl between each addition.

Add the flour mixture to the wet ingredients and mix on low speed until just combined. Scrape the sides and bottom of the bowl.

Add the sour cream and vanilla to the batter and mix until just combined. Scrape the sides and bottom of the bowl.

Add half of the batter to the prepared bundt pan.

Sprinkle the pecan filling over the top of the batter.

Add the remaining batter to the pan, smoothing the top with a spatula,

Place the pan on the center rack of the preheated oven and bake for 65-70 minutes or until a skewer inserted in the middle comes out clean.

Place the cake in the pan on a wire rack for 5 minutes. Then, invert the cake onto a wire rack to cool completely.

Sift powdered sugar into a large bowl.

Add two tablespoons of milk and the vanilla to the powdered sugar, whisking until smooth.

If necessary add a little more milk to the galze to get the desired consistency.