1. In large food processor, pulse together flour and butter until butter is well combined and no large pieces remain. Add powdered sugar, egg yolks, whole egg and salt; process until dough holds together and forms ball. Divide dough in half; flatten into disks; wrap each in plastic wrap. Refrigerate for 1 hour.
2. Heat oven to 400 degrees F. Line 2 large baking sheets with parchment paper. On lightly floured surface, roll out half the dough to 1/8-inch thickness. Cut out with varying size pumpkin cutters, making equal amounts of each shape to sandwich cookies later (see Note). Using small aspic or mini cookie cutters (or freehand with small sharp knife), cut out faces in half the cookies. Gather scraps together and reroll. Using thin metal spatula, transfer cookies to parchment-lined baking sheets.
3. Bake batches of cookies in 400 degrees F oven for 8 to 10 minutes or until lightly browned around edges. Transfer cookies to wire rack; let cool completely. Repeat with remaining dough.Royal Icing:
4. In bowl, on low speed, beat together confectioners sugar, powdered egg whites and 6 tablespoons water until all ingredients are moistened. Increase speed to medium; beat until thick, about 6 minutes. Cover tightly with plastic wrap. Prepare second batch of icing, increasing water to 8 to 9 tablespoons to create thinner icing for painting on colors.
5. Remove 1/4 cup of thinner icing to small bowl; tint green. Divide remaining thin icing among 5 bowls: Tint one bowl light yellow, one light orange, one medium orange, one dark reddish orange and one black. Using thin icing spatula or small paintbrush, use green icing to paint pumpkin stems and leaves on cutout cookies. Let dry slightly. Use yellow and orange icings to paint the cutout pumpkins, and the black icing to paint the cutout cats. Let cookies dry at least 40 minutes.Meanwhile, divide and tint thicker icing:
6. Transfer 1/4 cup thick icing to small bowl and tint black. Divide remaining icing into 3 bowls. Tint one bowl light orange to match thin light orange icing, one bowl medium orange, and one bowl reddish brown. Transfer thick tinted icings to pastry bags fitted with medium-size round tips. Outline cookies; pipe ridges on pumpkins, using some matching colors and varying others. Outline cat cookies and eye cutouts with thick black icing. Pipe on nose and whiskers with reddish orange or light orange. Let cookies dry for at least 1-1/2 hours.Filling:
7. While cookies are drying, in large bowl, beat together confectioners sugar, shortening, vanilla and the 1/4 cup water until smooth and good spreading consistency, about 2 minutes. Divide filling in half between 2 bowls (1-3/4 cups in each). Tint one half of filling medium yellow. To other half of filling, add 1/2 cup cocoa powder and 2 tablespoons water. Cover tightly with plastic wrap until ready to assemble cookies.Assemble:
8. Spread filling over rounded tops of solid cookies, using about 3 tablespoons for 4-inch cookies, 2 tablespoons for 3-1/2 inch and scant 1 tablespoon for 2 inch. Place matching cutout cookies on top and gently sandwich together.Note:
9. To make cat cookie (if cutter is unavailable), use 3-1/2-inch pumpkin shape; cut off top stem. Add 2 triangular pieces of cookie dough to form the ears. Cookie Cutters: Pumpkin cutters and mini cookie cutters are available through Wilton Cake Decorating: 1-800-794-5866 OR: www.wilton.com. Aspic cutters, liquid food paste gel colors, and powdered egg whites are available at New York Cakes: 1-800-942-253.