In a medium mixing bowl, whisk together the all-purpose flour, baking powder, and salt until well combined. Set aside.

In the bowl of a stand mixer fitted with the paddle attachment, cream the softened butter, granulated sugar, and brown sugar on medium speed for approximately 3 minutes, until the mixture becomes light and fluffy.

Add the egg and maple extract to the butter-sugar mixture. Beat on medium speed until well incorporated, about 30 seconds.

Gradually add the dry ingredient mixture to the wet ingredients, mixing on low speed until just combined. Scrape down the bowl as needed to ensure all components are evenly incorporated.

Divide the dough into two equal portions, form each into a disk, wrap in plastic wrap, and refrigerate for at least 1 hour to firm the dough.

Preheat the oven to 375°F (190°C). Line baking sheets with parchment paper.

Remove one dough disk from the refrigerator. On a lightly floured surface, roll the dough to approximately ¼-inch thickness. Using a maple leaf cookie cutter, cut out cookies and transfer them to the prepared baking sheets.

Bake in the preheated oven for 8–10 minutes, or until the edges are lightly golden. Do not overbake. Allow cookies to cool on the baking sheets for 3 minutes before transferring to a wire rack to cool completely.

In a clean bowl, beat the softened butter until smooth. Add the confectioners’ sugar and maple syrup, then continue beating until the filling is light, smooth, and creamy.

Spread a layer of the maple cream filling onto the bottom (flat side) of one cookie. Place a second cookie, flat side down, on top to create a sandwich. Repeat with the remaining cookies and filling.