1. Preheat the oven to 350 degrees Fahrenheit. Spray a standard size bundt cake pan with baking spray or grease it with butter or oil.

Streusel:

1. Combine the flour, granulated sugar, 1/4 cup brown sugar and cinnamon in a food processor.
2. Remove 1 1/4 cup of this mixture and put it into a small bowl. Add the remaining 1/4 cup of brown sugar to this mixture. Set aside. This will be the Streusel Filling used inside the cake.
3. Add the butter and pecans to the food processor and pulse about 10 times, until you have coarse crumbs. This will be the Streusel Topping.

Cake:

1. The butter is much easier to cut when it’s cold, so do it when it comes right out of the refrigerator and set aside until it softens a bit.
2. Whisk the eggs, 1 cup sour cream and vanilla extract in a medium bowl and set aside.
3. In the bowl of a standing mixer (you can also use a large bowl and a hand mixer), combine the flour, sugar, baking powder, baking soda and salt until combined.
4. Add the cubed butter and the remaining 1/2 cup sour to the dry ingredients. Mix on low speed until and the mixture is moistened and you still see some chunks of butter. Increase the speed to medium and mix until it all comes together. Scrape down the side of the bowl to make sure it’s all evenly combined.
5. Add the egg mixture in 3 additions on medium speed until the batter is smooth.
6. Spread 2 cups of the batter in the bottom of the prepared bundt pan. Sprinkle half of the streusel filling on top of it. Repeat with another 2 cups of batter and then the remaining half of streusel topping, finishing with the remaining batter. Sprinkle the streusel topping (with the butter and pecans) over the last layer of the bundt cake.
7. Bake in the preheated oven for 45 min – 1 hour, until a wooden skewer inserted into the center of the cake comes out clean.
8. Cool the bundt cake in the pan for 15-30 minutes, then invert it onto a serving plate.