In a large mixing bowl, pour the sweetened condensed milk and thawed pink lemonade concentrate. Whisk or beat until they are fully combined. The mixture should look smooth and creamy, with no streaks of concentrate left. This base creates the sweet-tart flavor that makes the pie refreshing.
Take the thawed whipped topping and gently fold it into the lemonade mixture using a spatula. Do this slowly to keep the filling airy and fluffy. Folding instead of stirring prevents the mixture from becoming too heavy and gives the pie its soft, mousse-like texture.
Pour the prepared filling into the 9-inch graham cracker crust. Spread it evenly with a spatula so that the surface is smooth. The crust holds the creamy filling and gives the pie a nice bite in every slice.
Place the pie in the refrigerator for at least 2 hours. This step allows the filling to set properly. If you want it firmer, leave it overnight. Chilling is key to achieving the right consistency for slicing and serving.
Once the pie is set, slice it into even pieces. Serve chilled for the best taste. You can garnish with lemon slices, fresh berries, or a little extra whipped topping if you like. It’s a refreshing dessert perfect for hot days.