1. Have ready a 9-inch pie plate (24cm) with removable bottom. I use a metal tart pan with 1-inch sides because it's a short pie, so if you use the traditional glass pie plate or ceramic pie dish, the crust won't reach the top of the pan edges unless you use a smaller-sized pan.
2. Preheat oven to 350º F /180ºC.
3. Crumbs: the easiest way is to use a food processor to finely grind the graham crackers or the pretzels. 

For the crumb crust:

1. Mix ground cookies or pretzels in a medium bowl with the melted butter until it has the texture of wet sand. If it’s too dry add an extra teaspoon of melted butter or two. It should be on the wetter side to firm up. 
2. Dump this crumb mixture in the pan and press onto the sides of the pan and bottom, making sure you don’t miss the angles where the bottom and sides meet.
3. Start with the edges and work your way up to the center of the pan, it’s the best way to make sure you don’t run out of cookie mixture for the angles and sides. You can use your hands (my way) or a measuring cup together with your hand to press the sides and create a compact wall up the sides. Make sure it’s well pressed and no spots remain without cookie mixture.
4. Bake for 10 minutes, until it starts to dry and brown. Reserve on a wire rack while you make the filling.
5. Keep the oven turned on.

For the filling:

1. Pour the condensed milk into a large bowl, add the egg yolks and mix with a wire whisk or spatula. Don’t beat.
2. Add the lime juice and mix well. The mixture will thicken almost immediately.
3. Add the tequila, liquor, and lime zest and mix well.
4. Pour the condensed milk mixture into the prepared crust (no need to let the crust cool completely, it can still be warm) careful not to overflow it.
5. Put the pie back into the oven and bake for 7-10 minutes more, until it firms up but the center still juggles slightly. Watch it carefully.
6. Let cool completely on a wire rack, wrap in plastic, or put a piece of plastic wrap on top lightly touching the surface and refrigerate for a few hours or overnight.
7. Take it out of the fridge 10 minutes before ready to serve it so it's easier to remove from the pie dish. Carefully unlock the sides of the pan from the crust (it might feel as though it's stuck but it will be fine) and place it on a smooth surface. I usually leave the bottom of the pan and transfer it to the serving plate, but you can very carefully lift the pie with a large spatula and transfer it to the serving plate.
8. Grate some zest on top and sprinkle with a bit of sea salt if you want to.
9. Or serve it with slightly sweetened whipped cream.