Preheat your oven to 350°F and grease two 8-inch round cake pans.
In a bowl, mix flour, baking powder, salt, and espresso powder.
In another bowl, cream together butter and sugar until light and fluffy.
Beat in the eggs one at a time, followed by the vanilla extract.
Alternate adding the dry ingredients and milk to the wet ingredients, mixing until smooth.
Pour the batter evenly into the prepared pans and bake for 30-35 minutes or until a toothpick comes out clean.
While the cakes bake, beat egg whites with an electric mixer until soft peaks form.
Add sugar, vanilla, and cream of tartar, continuing to beat until stiff peaks form.
Remove the cakes from the oven and let them cool completely.
Spread a layer of meringue on top of each cake and bake for an additional 10–12 minutes until golden brown.
Layer the meringue-topped cakes, serve, and enjoy the unexpected espresso and meringue magic.