Preparation

1. Add the sweetened condensed milk, lime juice, and lime zest to a large bowl and whisk to combine. Set aside.
2. In a separate bowl, beat half of the whipping cream and 1 teaspoon of the vanilla with an electric mixer on medium-high until soft peaks form.
3. Fold 1/3 of the whipped cream mixture into the sweetened condensed milk mixture until combined. Fold in remaining whipped cream mixture in two additions.
4. Layer bottom of a 9x13-inch baking dish with graham crackers, breaking some apart as needed to create a single layer.
5. Spread half of the sweetened condensed milk/cream mixture over the graham crackers. Cover with another layer of graham crackers, followed by the remaining cream mixture. Top with remaining graham crackers and place in the fridge to chill while you work on the topping.
6. In a large bowl, beat the remaining whipped cream, powdered sugar, and remaining vanilla on high with an electric mixer until medium peaks form.
7. Spread over final layer of graham crackers and cover dish with plastic wrap. Place in fridge and chill overnight.
8. When ready to serve, garnish with lime slices or zest, if desired. Enjoy!