Preheat oven to 375°F (190°C). Lay bacon slices on a parchment-lined baking sheet and sprinkle with 2 tablespoons brown sugar. Bake for 15-20 minutes until crispy, then cool and chop into small pieces.
Reduce oven temperature to 350°F (175°C). Line a 12-cup muffin tin with paper liners.
In a medium bowl, whisk together flour, baking powder, baking soda, and salt.
In a large bowl, cream 0.5 cup butter with granulated and brown sugars until light and fluffy. Beat in the egg, sour cream, 0.25 cup maple syrup, and vanilla extract.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Do not overmix.
Divide batter evenly among muffin liners. Bake for 18-20 minutes or until a toothpick inserted in the center comes out clean. Transfer to a wire rack to cool completely.
To make the frosting, beat 1 cup softened butter until creamy. Gradually add powdered sugar, 2 tablespoons maple syrup, and sea salt. Whip until light and airy.
Pipe the frosting onto the cooled cupcakes and garnish with the chopped candied bacon pieces.