Preheat oven to 350 degrees F. Butter a 9-inch springform pan or pie plate. Set aside.
Sift flour, baking powder, and salt together into a medium bowl. Set aside.
Put butter and 1 cup sugar in the bowl of an electric mixer fitted with the paddle attachment. Mix until pale and fluffy, about 3 minutes. Add in egg, buttermilk, vanilla, and almond extract. Mix until combined.
Gradually mix in the dry ingredients. Transfer batter to prepared pan. Arrange cherries on top of batter.
To make the almond streusel topping-in a small bowl combine flour, brown sugar, almond paste, butter, and salt. Mix together with your fingers until crumbly. Top the cake with streusel topping.
Bake cake for 10 minutes. Reduce oven temperature to 325 degrees. Bake until cake is golden brown and firm to the touch, about 50-55 minutes. Let cool in pan. T
While the cake is cooling, make the glaze. In a medium bowl, combine powdered sugar, almond extract, and just enough of the milk to make a pourable glaze. Drizzle over the cake and garnish with toasted almond slices, if using.
Cut the cake and serve.
Note-the cake will keep up to 2 days, stored in an air-tight container on the counter.