Makes about 16 bars
2 1/4 sticks butter, melted and cooled
2 cups golden brown sugar, packed
3 large eggs
2 teaspoons vanilla
2 cups flour
2 tablespoons espresso powder
1 teaspoon baking powder
1/2 teaspoon baking soda
1/2 teaspoon salt
3/4 teaspoon ground cinnamon
1/4 teaspoon ground nutmeg
1 1/2 cups chopped white chocolate (or white chocolate chips)
1/2 cup sliced almonds
1 cup confectioners' sugar
2 tablespoons Bailey's Irish Cream
2-3 teaspoons whole milk or cream
Preheat the oven to 350F degrees. Line a 9X13-inch baking pan with aluminum foil so that there is a 1-inch overhang, and spray the foil with nonstick baking spray.
In the bowl of an electric mixer fitted with the paddle attachment, beat the butter and brown sugar at medium speed until creamy, 3-4 minutes. Add the eggs, one at a time, beating well after each addition, and continuing to beat for 1 minute more after the last egg is added. Beat in the vanilla.
In a medium bowl, whisk together the flour, espresso powder, baking powder, baking soda, salt, cinnamon, and nutmeg. Add the dry ingredients to the wet ingredients, mixing on low speed until incorporated. Remove the bowl from the mixer and stir in the white chocolate chips.
Pour the batter into the prepared pan, smoothing the top with an offset spatula. Sprinkle the almonds evenly over the top. Bake until the top is set and a toothpick inserted into the center of the pan emerges clean, 24-28 minutes. Transfer the pan to a wire rack to cool completely.
For the Irish Cream Glaze, whisk together the confectioners' sugar an the Bailey's in a bowl until thoroughly combined. Add enough of the milk/cream to achieve a thick glaze that is still of drizzling consistency. Transfer the glaze to a small zip-top bag, seal, and snip a small corner off the end. Use this as a "piping bag" to drizzle the glaze over the bars.
Allow the glaze to dry for at least 30 minutes, then cut into squares and serve.