Softening Butter: Start by taking the butter out of the fridge to soften at room temperature. Cut it into small pieces and leave it for about 30-60 minutes until it can be easily pressed with your finger.

Mixing Butter and Powdered Sugar: Place the softened butter into a mixing bowl and add the powdered sugar. Mix gently with a spatula to avoid sugar splashing, then use an electric mixer on low speed to blend the butter and sugar until smooth. Gradually increase the speed to medium and mix until the butter becomes fluffy and light. This should take about 3-5 minutes.

Adding Egg Liquid: Beat the whole egg liquid and add it in two portions to the whipped butter mixture. After each addition, mix on low speed until fully absorbed before adding the next. Be careful not to add all the egg liquid at once to avoid separation.

Adding Coffee Liquid: Pour the prepared coffee liquid into the butter-egg mixture. Mix on low speed until well combined and the coffee flavor is fully incorporated.

Sifting Dry Ingredients: Sift together the cake flour and cocoa powder. Add them to the butter mixture and gently fold using a spatula. Mix until the dough forms, but don't overmix, or the cookies will lose their crispiness.

Kneading the Dough: Wearing disposable gloves, knead the dough into a smooth ball. If the dough is too sticky, sprinkle a little more cake flour, but don't overdo it, as it could affect the cookie texture.

Shaping the Cookies: Divide the dough into 40g portions, roll them into balls, and place them on a baking sheet. Flatten the balls lightly with a rolling pin, creating an indentation in the center. Leave space between the cookies, as they will expand during baking.

Baking: Preheat the oven to 170°C (340°F). Bake the cookies in the middle of the oven for about 20 minutes. Watch the color change; when the edges turn slightly darker and the center is no longer soft, the cookies are done. Let the cookies cool completely on a wire rack.

Softening Cream Cheese: Take the cream cheese out of the fridge to soften at room temperature for 30-60 minutes until it can be easily pressed with your finger.

Whipping Cream Cheese and Sugar: In a mixing bowl, add the softened cream cheese and granulated sugar. Mix on low speed with an electric mixer until the sugar is fully dissolved and the mixture becomes smooth, about 2-3 minutes.

Adding Heavy Cream and Coffee Liquid: Add the heavy cream and coffee liquid to the cream cheese mixture. Stir gently with a spatula, then whip on low speed until the filling is smooth and holds its shape. Be careful not to overwhip.

Piping the Filling: Once the coffee cookies have cooled, fill a piping bag (or a plastic bag with a small corner cut off) with the tiramisu cream cheese filling. Pipe the filling into the center of each cookie until it's level with the edges.

Decorating: Sift cocoa powder evenly over the tops of the filled cookies for a beautiful finish. Using a sieve helps ensure the cocoa powder is evenly distributed, giving the cookies a polished, professional look.