Crust
36 vanilla wafer cookies
3 tablespoons sugar
4 tablespoons (1/2 stick) unsalted butter, melted

Filling
3 large eggs
1 14-ounce can sweetened condensed milk
Finely grated zest of 2 lemons
1/2 cup fresh lemon juice
Confectioners' sugar for dusting
8 candied violets (optional)

1. For the crust, adjust an oven rack to the center position and preheat the oven to 325°F.

2. Put the cookies in a zip-top plastic bag and crush with a rolling pin to make fine crumbs. Transfer the crumbs to a bowl and add the sugar and melted butter. Combine well with a fork. Press the mixture into the bottom and up the sides of a 9-inch tart pan with a removable bottom. Bake for 15 minutes, or until golden brown.

3. Meanwhile, for the filling, whisk the eggs in a medium bowl. Whisk in the condensed milk and the lemon zest. Very gradually whisk in the lemon juice.

4. When the crust is ready, remove it from the oven and pour in the filling. Return the pan to the oven and bake for another 30 minutes, or until the filling has puffed slightly and is set. Let cool completely on a wire rack.

5. Remove the rim of the pan and set the tart, still on the pan bottom, on a serving platter. Refrigerate for several hours, or overnight, before serving.

6. To serve, dust the tart with confectioners' sugar and decorate with the candied violets, if desired. Serve cold.