Preheat oven to 350 degrees and grease or line 12 muffin cups. Combine pecans, brown sugar and cinnamon in a small bowl, set aside.

In a large bowl combine flour, sugar and salt. Just give it a little stir with your spoon or spatula.

Take 8 tablespoons of your butter, slice into small pieces and drop into flour. Using pastry blender, mix butter into the flour until butter is small and crumbly. It only takes a minute or two.

Remove 1 cup of flour mixture and add it to brown sugar mixture.

Stir with a fork to blend and add in remaining 2 tablespoons of butter, you can melt the butter or just soften it in the microwave (this is what I did) creating a nice crumb streusel topping. Remove 3/4 cup of streusel and set aside.

Add baking powder and baking soda to remaining flour mixture.

Combine egg, sour cream and vanilla till well blended and creamy. I did this in the 2 cup measuring cup I used to measure my sour cream. Less dishes to wash up.

Add sour cream mixture to flour mixture and stir just till all combined and moist. Batter will look lumpy. Sometimes lumps are good. This is one of those times.

Now add the 3/4 cup of streusel topping to your batter, just fold it in so it's evenly distributed.

Spoon batter evenly into muffin tins.

Now start topping with the streusel. You'll need to press the streusel into the batter a bit to keep it all in.

Place in oven and bake for 18-25 minutes. Start checking at 18 minutes by inserting a toothpick, the only thing that should be on the toothpick might me some of the crumb topping. Mine took about 22 minutes.

Remove from oven and let cool for 5 minutes before removing to wire racks.