Grease a 9-inch pie dish with butter or shortening.
Melt the butter in the microwave in 30-second increments until melted.
7 tablespoons butter
Crush the graham crackers in a food processor into fine crumbs.
11 graham crackers
Pour in melted butter while running the processor on low until crumbs look like wet sand.
Press crumbs firmly into the bottom and sides of the pie dish. Freeze for 15-20 minutes.
Make the filling
In a large bowl, whisk together sweetened condensed milk and pink lemonade concentrate until smooth.
14 oz sweetened condensed milk, 6 oz can pink lemonade concentrate
Add 3 drops red food coloring (if using) and whisk to combine.
3 small drops red food coloring
Fold in thawed whipped topping until fully mixed.
8 oz whipped topping
Fill and freeze
Pour filling into the frozen crust. Cover with plastic wrap and freeze for at least 6 hours or until set.
Top with whipped cream and lemon slices to serve.
Whipped cream for topping
Notes
This pie will soften quickly at room temperature, so I recommend keeping it in the freezer after you’ve served the desired number of slices to keep it from getting too soft.
Use a flat-bottom glass or measuring cup to press the crumbs firmly into the pie dish. That will ensure that the crust won’t fall apart when the pie is sliced.