Prep the ingredients per the instructions above.
Preheat the oven to 350°F (176°C).
Mix together the mayo, mustard, poppy seeds, grated onion, horseradish, and Worcestershire. Taste the dressing and adjust the ingredients however you wish.
To assemble, spread the sauce inside the top and bottom of each bun. On the bottom bun, layer provolone, roast beef, and American cheese, and place the top bun on top. Repeat for remaining portions.
Wrap each sandwich in aluminum foil, and put them on a baking sheet in the oven until the buns are slightly crusty and the cheese is melted, about 10 minutes.
Mix the iced tea and lemonade.
Serve the sandwich with carrot sticks, ranch, and arnold palmer.