1. Prepare the Dough

– Preheat your oven to 350°F (175°C).

– In a medium bowl, whisk together the flour, baking powder, and salt.

– In a separate large bowl, cream the butter and sugar together until light and fluffy, about 3-4 minutes.

– Add the eggs, vanilla extract, and lemon zest (if using). Mix until well combined.

– Gradually add the dry ingredients to the wet ingredients, alternating with milk, starting and ending with the dry ingredients. Mix until just combined—do not overmix.

– Chill the dough in the refrigerator for 30 minutes to firm it up.

2. Shape the Cookies

– Roll the dough into tablespoon-sized balls and place them on a parchment-lined baking sheet. Leave about 2 inches between each cookie for spreading.

– Flatten each ball slightly with your fingers or the back of a spoon to form round discs.

– Bake for 10-12 minutes or until the edges are lightly golden but the centers are soft. Don’t overbake—remember, they will continue to cook on the sheet after removal.

– Allow the cookies to cool completely on a wire rack before frosting.

3. Make the Chocolate Frosting

– In a small saucepan, combine the unsweetened cocoa powder, powdered sugar, and butter. Add milk a little at a time, stirring constantly until the mixture is smooth and glossy.

– Once melted and smooth, remove from heat and stir in the vanilla extract.

4. Make the Vanilla Frosting

– In a separate bowl, whisk together powdered sugar, milk, and vanilla extract to create a smooth, spreadable glaze.

– Add more milk if you need a thinner consistency, or more powdered sugar for a thicker glaze.

5. Frost the Cookies

– Once the cookies have cooled, spread a generous layer of the chocolate frosting on one half of each cookie.

– On the other half, spread the vanilla glaze. You can use a small offset spatula or the back of a spoon to get a smooth, even layer of frosting on each side.

– Allow the frosting to set for about 30 minutes at room temperature, or 10-15 minutes in the fridge.

Serving and Storing:

– Serve the cookies once the frosting is set. They are perfect for a cozy coffee break or as part of a dessert platter at a party.

– Store any leftovers in an airtight container at room temperature for up to 5 days. To keep them fresher longer, you can also freeze the cookies for up to 3 months—just wrap them individually in plastic wrap and store in a freezer-safe bag.