Preheat oven to 350 degrees. Butter a 13 by 9-inch baking dish (for thinner bars use a 15 by 10-inch baking dish). In a mixing bowl, whisk together flour, baking powder and salt, set aside. In the bowl of an electric stand mixer fitted with the paddle attachment, whip together butter and sugar until pale and fluffy. Mix in eggs one at a time, then blend in vanilla and almond extracts. With mixer set on low speed, slowly add in dry ingredients and mix until combined. Reserve and set aside 1 1/2 cups batter then spread remaining evenly into prepared baking dish. Top with cherry pie filling spreading into an even layer. Dollop small spoonfuls of the remaining batter evenly over top. Bake in preheated oven about 30 - 37 minutes (near lesser time for 15 by 10 baking dish and greater time for 13 by 9). Remove from oven and allow to cool completely on a wire rack.
For the glaze:
In a small mixing bowl whisk together all glaze ingredients adding enough half and half to reach desired consistency. Pour into a resealable bag, seal bag and cut a small tip from one corner then drizzle over top of cooled bars. Allow glaze to set (to set it quicker chill in freezer) then cut into squares.