Part 3/5:
Prepare the Dough: Start by creaming the butter and powdered sugar in a large mixing bowl until light and fluffy. This process incorporates air into the mixture, giving the cookies a nice texture.
Add the Eggs and Oils: Next, add the egg and the oil to the butter mixture. Mix until well combined. After that, incorporate the vanilla sugar, followed by the coffee and water mixture. Stir until the batter becomes smooth.
Combine the Dry Ingredients: In a separate bowl, whisk together the flour, cornstarch, baking powder, and salt. Gradually add this dry mixture to the wet ingredients. Stir gently until a cohesive dough forms. Be careful not to overmix, as this can lead to tougher cookies.