Place the 2 cups of softened salted butter and 2 cups of granulated sugar in the bowl of a mixer. The butter should yield when pressed with a finger while still feeling cool rather than warm.
Beat the butter and sugar together on medium-high speed for approximately 3 minutes, or until the two ingredients are thoroughly blended.
Add the 2 tablespoons of vanilla extract and both eggs to the creamed butter mixture.
Continue mixing for approximately 3 minutes, until the dough mixture becomes noticeably lighter and fluffy. The substantial quantity of vanilla contributes both flavor and moisture to the cookies.
Mix in the 4 teaspoons of baking powder until evenly incorporated.
Add the 6 cups of all-purpose flour gradually, working in approximately 2 cups at a time. Once the flour is introduced, avoid excessive mixing; blend only until no dry flour remains and a cohesive dough forms.
The completed dough should feel firm without becoming dry or crumbly. If it seems unusually dry, mix in a very small quantity of vanilla extract or milk, beginning with 1 teaspoon.
Transfer a portion of dough to a prepared work surface and roll it to approximately 3/8 inch thick.
Cut the rolled dough into the desired shapes with cookie cutters. Collect the remaining scraps, roll them out again, and continue cutting until the dough has been used.
Preheat the oven to 350°F (175°C).
Arrange the cut cookie shapes on a baking sheet and bake for 6–10 minutes, adjusting the baking time according to their size and thickness.
Thicker cookies generally require approximately 9–10 minutes, while smaller or thinner shapes may be ready after 6–7 minutes. Remove the cookies when they are set and the edges are only beginning to develop a faint golden color.
Do not overbake, as additional baking can cause the cookies to become dry.
Allow the baked cookies to cool completely before decorating.
Finish the cooled cookies with buttercream frosting. The frosting may be tinted as desired for holiday decorations and provides a smooth, creamy topping.