3/4 cup plus 2 T packed dark brown sugar
1/4 cup chopped pecans
1/2 tsp cinnamon
1 cup flour
1 cup whole-wheat flour
1 tsp baking soda
1/2 tsp salt
1/4 cup canola oil
1 cup unsweetened applesauce
1 tsp vanilla
3/4 cup buttermilk
1 apple, cored, peeled, and cut into 1/4-inch pieces
Preheat oven to 400 degrees. Prepare 12-cup muffin pan.
In a small bowl, mix together 2 T of the brown sugar, pecans and cinnamon. Set aside.
In medium bowl, whisk together both flours, the baking soda, and salt.
In a large bowl, whisk the remaining 3/4 cup brown sugar and the oil until combined. Add the eggs, one at a time, whisking well after each addition. Whisk in the applesauce and vanilla. Stir in the flour mixture in two batches, alternating with the buttermilk, just until combined. Gently stir in the apple pieces.
Pour the batter into the muffin pan, filling each about 2/3 full, and sprinkle evenly with the pecan mixture. Bake 20 minutes.
Let cool on wire rack for 15 minutes and then remove from pan.