Preheat your oven to 350°F (175°C) and lightly grease three or more donut pans.

In a large bowl, whisk together the flour, granulated sugar, baking powder, salt, cinnamon, and chopped pecans until no lumps remain.

In a separate medium bowl, whisk together the milk, maple syrup, eggs, melted butter, and vanilla extract until well combined.

Pour the wet ingredients into the dry ingredients and mix with a whisk until just combined, being careful not to overmix.

Transfer the batter to a piping bag or Ziploc bag, snip off a small corner, and pipe the batter evenly into the greased donut pans, filling each cavity about two-thirds full.

Bake for 10-12 minutes, or until the donuts spring back when lightly touched and the edges are lightly golden.

Remove the pans from the oven, let the donuts cool in the pans for about 5 minutes, then invert them onto a wire cooling rack to cool completely.

While the first batch cools, prepare and bake subsequent batches, ensuring to rinse and regrease hot pans.

Once all donuts are baked and cooling, whisk together powdered sugar, maple syrup, milk, and vanilla extract in a medium bowl until smooth, adjusting milk or powdered sugar for desired consistency.

Once completely cool, dip the top of each donut into the maple glaze, allow excess to drip off, and then place them on the wire rack.