Heat refried beans in a microwave-safe bowl in a microwave oven until hot, stirring frequently, about 3 minutes. Spread beans onto the bottom of a serving platter; refrigerate until the beans are cooled completely, about 10 minutes.
Spread guacamole in a layer atop the beans. Spread sour cream atop the guacamole. Sprinkle cheese over the sour cream; top with tomatoes.
Cover platter with plastic wrap and refrigerate until cold, about 30 minutes.