Preheat your oven to 350°F (175°C) and line an 8-inch square baking pan with parchment paper, lightly greased.

In a large mixing bowl, whisk together the all-purpose flour, granulated sugar, brown sugar, baking soda, baking powder, salt, and ground cinnamon until well blended.

In a separate bowl, mix the melted unsalted butter, pure maple syrup, milk, large egg, and vanilla extract until smooth.

Gently fold the wet mixture into the dry ingredients until just combined, taking care not to overmix.

Transfer the batter into the prepared baking pan, smoothing the top with a spatula.

Bake for 20-25 minutes or until the edges are golden brown and a toothpick comes out clean.

Remove from the oven and cool in the pan for about 10 minutes before lifting out to cool completely.

Slice into squares or rectangles and serve warm or at room temperature.