1-First Step: Prepare the dough. In a large bowl, cream 1/2 cup softened butter with 1 cup sugar until light and fluffy, about 2 minutes. Beat in 2 eggs one at a time, then add 1 tsp vanilla. In another bowl, whisk 2 cups flour, 1 tsp baking powder, and 1/2 tsp salt. Gradually mix dry into wet. Add green food coloring drop by drop until tree-green. Wrap dough and chill 1 hour. This rest prevents spreading. For gluten-free, swap flour now.

2-Second Step: Roll and cut shapes. Preheat oven to 350°F. Line two baking sheets with parchment. Roll chilled dough to 1/4-inch thick on floured surface. Use a 3-4 inch Christmas tree cookie cutter to cut shapes in graduating sizes if possible, or uniform and trim post-bake. Place 1 inch apart. For vegan dough, same process works seamlessly.

3-Third Step: Bake the cookies. Bake 8-10 minutes until edges firm but centers soft. They firm as they cool, mimicking cake texture. Cool on sheet 5 minutes, then wire rack fully. Yields about 60 small trees worth. Watch closely to avoid browning; pale green suits the look. Low-cal tip: bake same time.

4-Fourth Step: Make the frosting. Beat 1 cup room-temp unsalted butter until creamy. Sift in 4 cups powdered sugar gradually. Add 2-3 tbsp heavy cream, 1 tsp vanilla, 1/2 tsp green gel coloring, pinch salt. Whip high 2-3 minutes for fluff. Chill 15 minutes. Adjust with milk if thick. Vegan: plant butter and cream shine here.

5-Fifth Step: Stack the trees. Select 3-4 cookies per tree, widest base. Spread 1/4-inch frosting layer on top of base, stack next, press gently 10 seconds. Chill 10 minutes between layers for stability. Repeat to top. Pipe brown trunk: mix cocoa into small frosting batch, apply base.

6-Sixth Step: Decorate like real trees. Dot ornaments with mini M&Ms or sprinkles using tweezers. Top with star candy dabbed with frosting. Dust powdered sugar through sieve for snow. Let set 30 minutes. Quick per tree: 5 minutes.

7-Final Step: Serve and enjoy. Arrange on platters. Stands 4+ hours room temp. Yields 20 trees. Perfect for holiday parties. Troubleshoot: if sliding, chill more.