In a large mixing bowl, whisk together 2 cups of all-purpose flour, 2 teaspoons of baking powder, 0.5 teaspoon of baking soda, 0.5 teaspoon of salt, and 0.5 teaspoon of ground nutmeg until evenly combined.

In another bowl, melt 0.5 cup of unsalted butter and allow it to cool slightly. Then whisk in 1 cup of granulated sugar, 2 large eggs, 1 cup of buttermilk, and 1 teaspoon of vanilla extract until smooth.

Gradually pour the wet mixture into the dry ingredients. Fold together with a spatula until just combined.

Preheat your oven to 350°F (175°C) and grease and flour a 9x13 inch baking pan.

Spread the batter evenly into the prepared baking pan. Bake for 20-25 minutes.

Remove the pan from the oven and let the bars cool for about 10 minutes. Transfer to a wire rack to cool completely.

In a mixing bowl, sift 1 cup of powdered sugar and whisk in 0.25 cup of pure maple syrup, 2 tablespoons of milk, 2 tablespoons of melted butter, 1 teaspoon of vanilla extract, and a pinch of salt until smooth.

Once the bars are cool, pour the glaze over the top and spread it evenly. Add your favorite toppings before the glaze sets.

Let the glaze set for 30 minutes to 1 hour before cutting the bars into squares.