Preheat oven to 375°F (190°C). Grease a doughnut pan.
In a large bowl, whisk together flour, sugar, baking powder, and salt.
In another bowl, mix milk, eggs, melted butter, maple syrup, and vanilla extract.
Combine wet and dry ingredients until just mixed. Fold in crumbled bacon.
Fill doughnut pan with batter. Bake for 12-15 minutes or until golden brown.
Let doughnuts cool slightly before removing from pan.
For the glaze, mix powdered sugar, maple syrup, and milk until smooth. Dip doughnuts in glaze.