Step 1

Preheat the oven to 350 degrees.

Step 2

For the crust, place the shortbread cookies in a food processor and pulse until you get fine crumbs.

Step 3

Toss the cookie crumbs together with melted butter and sugar.

Step 4

Press the crumbs into a 9-inch deep-dish pie plate.

Step 5

The crust will take 8-10 minutes to bake.

Step 6

Place the crust in the freezer while you prepare the filling.

Step 7

For the filling, stir together egg yolks, sweetened condensed milk, lemon juice (use fresh lemons if possible), and lemon zest.  Whisk until combined.

Step 8

Pour the filling into the crust and bake for only 15 minutes or until set.

Step 9

Remove the pie from the oven and allow it to cool completely.