SOAK corn husks in hot water 30 minutes or let stand overnight in room-temperature water. Prepare Tamale Dough recipe, adding the drink mix to the dough with the masa harina.
ASSEMBLE tamales by spreading 2 Tbsp. of the masa mixture (tamale dough) into a 3x2-inch rectangle down the center of each corn husk, leaving about 2 inches bare at the top of the husk. Spoon 1 Tbsp. of the pineapple and 1 tsp. of the brown sugar down the center of the masa mixture; fold over the sides of the husk and both ends to completely enclose the filling.
STAND tamales in a steamer basket in large pot filled 1/4 full with water. (Make sure tamales are not touching the water.) Bring water to boil; cover. Steam 1 hour or until tamales pull away from the corn husks, adding more water to the pot when necessary. Remove tamales from steamer basket; cool slightly. Top with thawed COOL WHIP Whipped Topping just before serving, if desired.