Prepare 3 9-inch cake pans by spraying them thoroughly with nonstick spray. Line the bottoms with parchment paper. Set aside.
Sift the dry ingredients into a large bowl: flour, baking powder, cornstarch, nutmeg, cinnamon, and cardamom. Set aside.
In a stand mixer, cream the 2 sticks of butter, 2 cups of sugar, and half cup honey until light and fluffy, at least 2 minutes, scraping the sides as you go.
Separate the 6 eggs: the whites need to go in a separate large bowl. (If you have 2 bowls for your stand mixer, use the other one). Set that aside.
Add the yolks to the butter mixture, one at a time, stirring in between each addition. Make sure you scrape the sides well. Beat until it is smooth and creamy.
In a small bowl, combine the milk, vinegar, and almond extract. It's okay if it curdles.
Add the milk mixture and the flour mixture alternately to the butter mixture, stirring after each addition until just combined.
Gently fold in the poppyseeds. Set aside.
Preheat the oven to 350 F.
Add the 1/2 teaspoon cream of tartar to the eggs whites. Using an electric mixer, beat the whites until soft peaks form; it will take several minutes.
Add the beaten egg whites to the cake batter in 3 additions, mixing until just combined.
Divide the batter evenly among the 3 prepared cake pans. Bake 30-40 minutes, or until a toothpick inserted in the center comes out clean. Check each cake, some may cook slower than others.
Remove from the oven and let cool 10 minutes. When you can handle the pans without burning yourself, remove the cakes to a wire rack. Peel off the parchment paper.
At this point, you can either freeze the cakes to frost later, or do it immediately. To freeze: While the cakes are still hot, wrap each cake tightly in plastic wrap, then in aluminum foil. Freeze for several hours, or up to 3 days. The night before you want to frost, place them in the fridge to defrost.
To frost immediately: let the cakes cool completely, then wrap tightly in plastic wrap and refrigerate until cold, at least an hour. It's easier to frost a cold cake.
To make the frosting: beat together the butter and sugar until a thick paste forms. Then add the extracts and half & half, adding more if it seems too thick. Beat until fluffy.
Spread about 1/2 cup frosting over each layer. Frost the top of the cake, then spread the excess down the sides.
Sprinkle the top with more poppyseeds, and pipe on the stars using a large star tip.
Notes
You can replace half the flour in this recipe with white whole wheat flour.Source: adapted from Bake at 350, who got it from Cake Ladies. As see on Catz in the Kitchen.