Special equipment: Toothpicks or skewers Garlic press Small, clean artist's paintbrush
For the cake, have ready a serving tray or foil-covered board at least 11 by 5 1/2-inches and 1 sturdy unpleated plastic ziptop sandwich bag. Cut one of the cakes in half. Remove and reserve 3/4 cup frosting. Scrape rest into a bowl and tint yellow (color will deepen slightly as it stands). Spoon 1/3 cup into ziptop bag. Cut 1 whole graham cracker in half. Sandwich 2 whole crackers and halved crackers with yellow frosting. Line up in middle of serving surface to create a long rectangle. Top crackers with dabs of frosting. Use some yellow frosting to glue the front of the truck (one of the cake halves) to the body (the full cake), and then glue the cab (second half of the cake) slightly centered on top. Set truck on stacked crackers to elevate. Cut 1 whole cracker in half lengthwise. Spread 1 long edge of each with yellow frosting and insert 2 inches from front on both sides, between bottom of the cake and stacked crackers, for running boards. With small spatula, frost windows with untinted frosting; reserve about 2 tablespoons. Frost truck and running boards with yellow frosting; reserve about 2 tablespoons. Fold 1 stick of gum in half lengthwise (don't press down on fold). Coat with remaining untinted frosting. Press into frosting on front of truck for a bumper. Press doughnuts into frosting for tires. With small scissors, round off ends of 2 sticks of gum. With rolling pin, roll out gum to widen slightly. Drape over front tires for fenders. Frost with reserved yellow frosting. Cut a thin slice off bottoms of gum drops, insert gumdrop headlights in place. Press 3 pieces of licorice lace onto each running board for treads, 2 pieces over headlights to outline, 4 pieces for grill, 2 for windshield wipers and 2 for door handles. Cut 1 cracker in half lengthwise. Press half into each side of cargo bed. Cut remaining cracker in half lengthwise; trim to 3 1/2-inch wide rectangle. Press in place for tailgate. Insert pretzel sticks for posts. Snip a small corner off ziptop bag. Squeeze frosting through opening to pipe outline of windows and doors. Let dry at least 4 hours. Sprinkle coconut grass around truck.
For marshmallow veggies, process marshmallows and 2 cups confectioners' sugar in a food processor until large crumbs form. Transfer crumbs to a microwave-safe bowl. Microwave on high 10 seconds. Carefully (mixture may be hot) start working crumbs with 1 hand, kneading, squeezing and pulling. As mixture becomes a slightly sticky paste, gradually work in remaining 1 1/2 cups confectioners' sugar, microwaving mixture a few times in 5 to 10 second increments to soften dough during kneading. When done, dough should be smooth and elastic. Fill a 13 by 9-inch baking pan or a tray with about 1/2-inch granulated sugar (to support and hold veggies as they dry). Break off about 1/4 cup dough at a time to knead in colors. Knead colors into the dough until completely blended. Make several shades of green for leaves (lettuce uses 3 shades, from dark to light green) and stalks, mixing in a little yellow for lighter shades. If needed, lightly moisten dough with water to make pieces stick to each other. Potatoes: Knead red and a little blue food color into dough until reddish brown. Form into ovals; make eyes with a toothpick. Carrots: Knead orange color into dough. Form carrots. Make ridges with side of a toothpick. For tops, roll green dough into thin strings. With toothpick, poke a hole in top of each carrot; insert tops. Radishes: Tint dough red. Form radishes. For leaves, press small balls of green dough flat, then score with back of a knife. Roll green dough into short stems; press onto leaves. Insert as for carrots. Turnpis: Form with white dough. Make leaves as for radishes, making longer stems. Insert as for carrots. Mix red and blue color in a cup intil violet; thin with water. Brush on top half of turnips. Lettuce: Use 3 shades of green dough. Start with a small ball of lightest shade. Press 2 or 3 darker green balls into lettuce leaves. Wrap around light-green ball. Press 2 or 3 balls of darkest green for outer leaves; wrap around lettuce head. Celery: Form a cylinder of pale yellow dough. Shape light-green dough into 2 or 3 celery stalks; wrap around cylinder. Flatten small balls of pale yellow dough. Cut leaves with a small sharp knife and tuck into top of celery bunch. Mark rib ridges with a sharp knife. Leeks: Form cylinders of white dough. Shape green dough into 2 or 3 rectangles for leaves; wrap around top 2/3 of cylinder. Cut tops of leaves as shown. For roots, press a small ball of white dough through a garlic press. Attach to leeks with water. Add yellow color to the violet-tinted water until violet turns brown. Brush on roots for soil
Recipe courtesy of Elizabeth Alston, Food Editor, Woman's Day Magazine