1-First Step: Prepare the mise en place Measure 2 ½ cups all-purpose flour, 1 tsp baking powder, and ½ tsp salt into a bowl. Sift together to prevent lumps, key for bakery style birthday cake cookies. Softening 1 cup unsalted butter takes 30 minutes at room temp. Have 1 cup granulated sugar, 1 large egg, and 2 tsp vanilla extract ready. For frosting later, set aside ½ cup softened butter, 2 cups powdered sugar, 1 tsp vanilla, and 2-3 tbsp heavy cream. Prep gel colors, Christmas sprinkles, mini chocolate chips. This setup keeps things smooth for busy parents or students.

2-Second Step: Cream butter and sugar Beat softened butter and sugar on medium speed for 2-3 minutes until fluffy. Scrape bowl sides. This incorporates air for soft chewy birthday cake cookies. Add egg and vanilla, mix until combined. For vegan, use flax egg here. Low-speed prevents splatter. Smells amazing already, hinting at the funfetti cookies delight.

3-Third Step: Combine dry and wet ingredients Add dry mix gradually to wet, stirring low speed until just blended. Dough forms soft ball. Overmix toughens, so stop soon. For gluten-free, extra chill helps. Wrap and chill 1 hour. This rests gluten for tender holiday funfetti cookies with sprinkles.

4-Fourth Step: Shape and bake the cookies Preheat oven 350°F. Line sheets parchment. Roll 1-inch balls (tablespoon scoop), place 2 inches apart. Bake 8-10 minutes until edges golden, centers soft. GF may need 9-11 minutes. Cool sheets 5 minutes, then racks fully. Makes ~48 cookies for 24 stacks. Perfect crisp-chewy balance in Christmas cookies.

5-Fifth Step: Make the buttercream frosting Whip ½ cup butter fluffy, add powdered sugar ½ cup at time. Mix vanilla, then cream till spreadable peaks. Tint portions red/green with gel. Vegan: plant butter works same. Pipe or spread ready.

6-Sixth Step: Assemble the mini cakes Pair cooled cookies by size. Spread or pipe frosting bottom cookie, top second. Frost tops smooth. Crumb coat first for pro look, chill 15 min.

7-Final Step: Decorate and serve Pipe green trees, red cherries from candy. Add sprinkles, chocolate chip candles. Royal icing details. Serve room temp. Store airtight. Total active 1 hour, impresses at parties. Adapt for dietary: all subs work here.