1 (4-serving-size) package instant vanilla pudding and pie filling
1 1/2 cups milk
1 (12-ounce) container frozen whipped topping, thawed
1 (14.4-ounce) package chocolate-flavored graham crackers
1 (16-ounce) container ready-to-spread white frosting
1/4 cup semi-sweet chocolate chips
1/2 teaspoon vegetable shortening
1. In a large bowl, whisk vanilla pudding mix and milk 1 to 2 minutes, or until thickened. Stir in whipped topping.
2. Place a single layer of graham crackers in the bottom of a 9- x 13-inch baking dish. Evenly spread one-third of pudding over graham crackers. Repeat layers of graham crackers and pudding 2 more times, ending with a layer of graham crackers. Cover and freeze 6 hours.
3. Spread frosting evenly over top.
4. In a small microwaveable bowl, melt chocolate chips and vegetable shortening 45 to 60 seconds, stirring until smooth. Place mixture in a small resealable bag, and cut off a small piece of the corner. Pipe lines of chocolate from top to bottom about 1 inch apart. Run a butter knife through the lines in the opposite direction, creating a zebra pattern. Serve immediately or cover and freeze until ready to serve.