Ingredients

5 1/2-ounce package shortbread cookies
2 tablespoons granulated sugar
1/4 cup butter, melted
1/2 gallon mint chocolate chip or pistachio ice cream, slightly softened
1/2 cup heavy (whipping) cream
1 tablespoon granulated sugar

Chocolate Shamrocks:
2 squares (2 ounces) semisweet chocolate

In the bowl of a food processor, place cookies; process until crushed; transfer to a small bowl. With a fork, stir in sugar and melted butter until crumbs are moistened.
In a 9-inch springform pan, press crumb mixture over the bottom; place in freezer until set; about 30 minutes. Spread ice cream evenly over crumb mixture; cover and freeze until firm, about 3 hours. Fifteen minutes before serving, in a medium bowl with an electric mixer, whip heavy cream and the 1 tablespoon sugar until stiff peaks form. Remove cake from freezer; pipe whipped cream around edge. Arrange three Chocolate Shamrocks in the center. Let cake stand at room temperature for 10 minutes before serving. Makes one 9-inch cake (12 servings).

Directions

To make Chocolate Shamrocks: Line a baking sheet with waxed paper. Make a shamrock template by drawing a 2-inch shamrock on cardboard; cut out. Using the shamrock template, trace three shamrocks onto waxed paper; set aside.

Melt 2 squares (2 ounces) semisweet chocolate. Scrape into a small, resealable plastic bag; snip off one corner from the bag to form a very small hole; trace shamrock outlines with chocolate, filling in centers with chocolate. Freeze until firm. When ready to use, remove carefully from waxed paper.