Preheat the oven to 350ºF and line two muffin pans with muffin liners or spray the tins with non-stick spray..

Whisk the flour, baking powder, salt, cinnamon, nutmeg, and ginger in a small bowl. Set aside.

In a large bowl, combine the wet ingredients by whisking the sugar, brown sugar, eggs, milk, oil, and maple extract together until well combined. Add in the mashed sweet potatoes and mix. 

Add the all-purpose flour into the wet mixture and stir until the batter is well combined. 

To make the pecan streusel topping, mix the dark brown sugar, pecans, and cinnamon in a small bowl. Stir together (this is the mix that will go in the middle of the muffins).

In another small bowl, mix the dark brown sugar, oats, flour, chopped pecans, salt and cinnamon and mix. Cut the butter into small cubes and add to the bowl. Use your hands and make the streusel into a crumbly mixture.

Assemble the muffins: start by lining a muffin tin with paper liners. Using a #30 cookie scoop, place one scoop of muffin batter in the bottom of each liner. 

Sprinkle about 2 teaspoons of the middle mixture on top, tap it down gently and cover it with another scoop of batter. Use the back of a spoon to spread the batter over the top of the center sugar/pecan mix. 

Top with a tablespoon of the streusel and gently press it into the batter to keep it from falling off during baking. Repeat until all the batter is gone. 

Place one muffin pan in the oven at a time and bake for 25-30 minutes or until a toothpick comes out cleanly. Remove and allow to cool for 5 minutes before transferring them to a wire rack to cool completely. 

Store any leftovers in an air-tight container for up to 3 days.