1. Heat the oven to 350°F. Grease an 8-inch square cake pan with cooking spray or softened butter. Line with a long piece of parchment paper that extends up and over two opposite sides of the pan.

2. Process the crackers, sugar, and salt in the bowl of a good processor until the crackers are finely ground. Pour in the butter and process until the mixture holds together when squeezed. Alternatively, you may place the dry ingredients in a sealed, zippered plastic bag, cover it with a dish towel and crush the crackers with a rolling pin (either by rolling or smashing). Transfer to a medium bowl and stir in the butter. Scrape the crumbs into the prepared pan and firmly press them into the bottom. Bake the crust for 16 to 18 minutes, until golden brown, rotating at the halfway point. Reduce the oven temperature to 325°F.

3. Meanwhile, combine all of the filling ingredients but the eggs in a large bowl and whisk until smooth. Gently whisk in the eggs and then a drop or two of food coloring, if using. Carefully press down on the edges of the hot crust with the bottom of a one cup dry measuring cup (this step adheres the crust to the pan and precludes the filling seeping underneath it), pour in the filling and bake for about 17 minutes, until the filling has set, but still jiggles just slightly in the center. Cool to room temperature, and then refrigerate until cold, about 2 hours. Serve slices directly from the pan with a generous dusting of confectioners’ sugar. The bars will keep tightly wrapped in the refrigerator for up to 3 days, but the crust will soften over time.