Preheat the oven to 350°F. Line 16 wells in muffin tins with paper liners.
Start the maple cupcakes: Cook the butter in a small skillet over medium heat for 2 to 3 minutes, swirling the pan occasionally, until the butter melts and the milk solids begin to brown and smell nutty. Set aside.
Combine the flour, baking powder, baking soda, and salt in a medium bowl.
Beat the browned butter, mayonnaise, brown sugar, and granulated sugar with an electric mixer until creamy. (You can either use a hand mixer or a stand mixer fitted with the paddle attachment.) Add the flour alternately with the milk in 3 additions, beginning and ending with the flour mixture. Stir in the vanilla extract and maple extract.
Divide the batter evenly between the muffin cups. Bake for 19 to 22 minutes or until a toothpick inserted in the center comes out clean. Let cool in the pan for 5 minutes then remove to wire racks to cool completely.
Meanwhile, make the maple frosting: Bring the butter, brown sugar, and maple syrup to a boil in a small saucepan over medium-high heat. Boil for 5 minutes, stirring constantly, until the mixture bubbles and the sugar is dissolved. Set aside to cool completely.
Beat the cooled butter mixture and the powdered sugar with an electric mixer until combined. Add the milk and maple extract and continue to beat until the frosting is creamy.
Pipe or spread the frosting onto the cooled cupcakes. Cut the candied bacon strips in half crosswise, and garnish each cupcake.