In medium bowl, whisk flour, baking powder and salt.Advertisement
In large bowl, beat butter and sugar until smooth. Beat in egg, then yolk and vanilla. Stir in flour mixture. Tint dough green with food coloring. Wrap dough in plastic; refrigerate 2 hours.
Heat oven to 350°F. Using a heaping teaspoon dough, shape into a 2-inch log. Place on ungreased baking sheet. With scissors held at a 45-degree angle, make 3 snips along the length of the log, on the top, at 1/2-inch intervals; do not cut completely through dough. Twist cut pieces in opposite directions, to form leaf-shaped pieces that are still attached to each other. Pinch top and bottom leaves slightly. Repeat with remaining dough. Decorate with one or two red candies per cookie.
Bake cookies at 350°F for 10 to 12 minutes, rotating pans halfway. Transfer clusters to racks to cool. Store at room temperature for up to 2 weeks.