Add crackers to food processor pulse until finely ground, pulsing 6 to 8 times. Add egg white, butter, and 3 tablespoons of the sugar. Pulse until well combined, about 4 more times.
Melt butter and separate one egg. Add melted butter, the egg white and 3 tablespoons of sugar to the crumbled crackers.
Scatter crumb mixture evenly on bottom of a 9” inch tart pan with a removable bottom. Firmly press crumbs on bottom and against sides of pan using a straight-sided glass or dry measuring cup.
Bake crust in pre heated oven until golden brown around the edges, 12 to 14 minutes.
Cool completely before adding filling.
