Nonstick spray
1 stick (8 tablespoons) unsalted butter
2 cups all-purpose flour
1 1/2 teaspoons baking powder
1/2 teaspoon baking soda
1/2 teaspoon fine sea salt
1/2 teaspoon freshly grated nutmeg
2/3 cup pure cane granulated sugar
2 large eggs
3/4 cup buttermilk
2 teaspoons pure vanilla extract
1/2 cup grade B maple syrup
2 tablespoons bourbon
1 cup confectioners' sugar
3/4 cup finely chopped toasted pecans