Step 1

Preheat oven to 350 degrees. Spray two 14-by-4-inch fluted-edge tart pans with removable bottoms with cooking spray. In a food processor, pulse crackers until finely ground (you should have 2 1/4 cups). Add butter and granulated sugar; pulse to combine. Divide mixture between pans and firmly press into bottoms and up sides. Bake until golden brown, 15 to 20 minutes.

Step 2

Just before removing crusts, whisk together eggs and yolks, then whisk in condensed milk, lemon juice, and salt. Remove baked crusts from oven and carefully divide filling between pans. Return to oven and bake until set, 12 to 15 minutes.

Step 3

Transfer to a wire rack and let cool completely. Refrigerate until cold, at least 2 hours and up to overnight. Remove from pans; dust with confectioners' sugar. Cut into fingers or squares; serve.