Combine crumbs with butter and 1 tbsp sugar; stir until sandy in texture. Divide between two pint-sized Mason jars or large coffee mugs. Pack crumbs down into bottoms.
Stir remaining ingredients together until smooth. Divide between vessels. Place in microwave for 2 minutes on high (if your microwave does not have a rotating plate, turn vessels 90° after 1 minute). Continue to cook for 30-second intervals until the tops appear dry.
Transfer to refrigerator for at least 1 hour before serving. The top will develop a dimple as it cools; top with a dollop of whipped cream to cover it up.