Lemon Icebox Pie Ice Cream

from Southern Living

3 to 4 lemons
2 c. half and half
14 oz. can sweetened condensed milk
3/4 c. coarsely crushed graham crackers
1 Tbsp. lemon zest

Grate zest from lemons to equal 1 Tbsp.  Cut lemons in half and squeeze juice from lemons to equal 1/2 c.  Whisk together half and half, sweetened condensed milk, and lemon juice.  Pour mixture into freezer container of a 1 1/2 quart electric ice cream maker and freeze according to manufacturers instructions.  Stir in graham cracker crumbs and lemon zest.  Transfer to an air-tight container.  Freeze 2 hours before serving.