Have all the ingredients at room temperature.
Position a rack in the lower third of an oven and preheat to 350°F (I80°C). Grease and flour the Acorn Cake-let Pan; tap out excess flour. To make the cake-lets, over a sheet of waxed paper, sift together the flour, baking powder, salt, cinnamon, ginger and cloves. Set aside.
In a small bowl, whisk together the milk and vanilla. Set aside.
In the bowl of an electric mixer fitted with the flat beater, beat the butter on medium speed until creamy and smooth, about 30 seconds.
Add the maple sugar and granulated sugar and continue beating until light and fluffy, 3 to 5 minutes, stopping the mixer occasionally to scrape down the sides of the bowl. Add the eggs a little at a time, beating well after each addition.
Reduce the speed to low and add the flour mixture in three additions, alternating with the milk mixture and beginning and ending with the flour. Beat each addition just until incorporated, stopping the mixer occasionally to scrape down the sides of the bowl.
Spoon 1 Tbs. batter into each well of the prepared pan, spreading the batter into the top part of each acorn. Bake until a toothpick inserted into the center of a cake-let comes out clean, about 10 minutes. Transfer the pan to a wire rack and let the cake-lets cool in the pan for 15 minutes.
Using a serrated knife, gently saw off any portion of each cake-let that rose above the edge of the pan.
Tap the pan gently on a work surface to loosen the cake-lets. Place a wire rack over the top of the pan, invert the pan onto the rack and lift off the pan. Wash and dry the pan and repeat with the remaining batter.
To make the frosting, in the bowl of an electric mixer fitted with the flat beater, beat the butter and cream cheese on high speed until light and fluffy, 2 to 3 minutes. Reduce the speed to low, add the maple syrup and confectioners' sugar and beat until combined, 2 to 3 minutes, stopping the mixer occasionally to scrape down the sides of the bowl. Set the frosting aside in a cool place.
Meanwhile, make the glaze: In a small saucepan over medium heat, combine the granulated sugar, maple syrup and water. Cook until the sugar has dissolved and the mixture is slightly thickened, 3 to 5 minutes. Remove from the heat.
Set the rack with the cake-lets over a sheet of waxed paper. Using a pastry brush, brush the warm cake-lets with the glaze. Put coarse sugar in a small bowl. Hold the base of a cake-let with your fingers and dip the top of the acorn into the sugar. Repeat with the remaining cake-lets. Let the cake-lets cool completely, at least 2 hours, before assembling or serving.
To assemble the cake-lets, spread about 1/2 tsp. frosting on the flat side of a cake-let.
Place its matching cake-let half, flat side down, on top. Repeat with the remaining cake-lets. Refrigerate until the frosting is set, about 30 minutes.
Makes 36 individual cake-lets or 18 assembled cake-lets.