**To prevent soggy muffins use tart apples good for baking, such as
Baldwin, Braeburn, Cortland, Fuji, Gala or Granny Smith.**
Preheat the oven to 350 degrees.
Line a 12-cup muffin-tin with paper liners.
For the Streuesel
In a medium bowl, combine chopped pecans, brown sugar, and cinnamon.
Mix well and set aside.
For the Muffins
In a large bowl, combine flour, sugar, and salt with a whisk.
Cut 8 tablespoons of butter into ½ inch cubes and sprinkle evenly over flour mixture. Using a pastry blender, cut the butter into the flour mixture until butter is oat-sized.
Remove 1 cup of the flour-butter mixture and stir into reserved brown sugar mixture until combined to make streusel; set aside.
Add baking powder and baking soda to remaining flour mixture and stir to combine.
In a liquid measuring cup, whisk together sour cream, egg, and vanilla.
Add liquids to muffin flour mixture and stir until just combined.
Add 3/4 cup of streusel mixture back into flour mixture and stir until streusel is just distributed throughout batter.
Gently fold apples into batter.
Melt the remaining butter and stir into remaining streusel mixture, until streusel resembles a crumble.
Divide batter among 12 muffin cups and sprinkle generously with streusel topping, crumbling with your hands to make some big chunks.
Bake 22 to 24 minutes, or until a toothpick inserted in the center of muffin comes out clean.
Allow to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
To make the glaze, whisk the confectioners' sugar, milk and vanilla extract together.
Drizzle over muffins.
Store in a sealed container for up to 2 days.
Notes
To prevent soggy muffins use tart apples good for baking, such as Baldwin, Braeburn, Cortland, Fuji, Gala or Granny Smith.muffins can be frozen for up to 3 months