Preheat the oven to 350°F (175°C) and make room in your fridge for the pie.

In a food processor, pulse graham crackers into fine crumbs.

Transfer crumbs to a bowl and mix with sugar and melted butter until combined.

Press the mixture into the bottom and up the sides of a standard-size pie pan.

Bake crust for 5 minutes, then remove and let cool.

In a medium bowl, combine lime zest, lime juice, tequila, and egg yolks using a mixer.

Add sweetened condensed milk and remaining sugar; mix on high for 1-2 minutes until thick.

Pour the mixture into the cooled graham cracker crust.

Bake for 15 minutes, or until the filling is set but slightly jiggly in the center.

Remove the pie from the oven and let it cool completely.

Refrigerate for at least 1 hour to chill and firm.

Serve chilled with sweetened whipped cream if desired.