If you are slicing the roast beef yourself, you can do so using a very sharp knife, a mandolin, or a meat slicer. I prefer the roast beef to be thinly sliced for this sandwich.
Start by adding your lettuce to the bottom bun.
Next, place on your cheese and then the sauce. The lettuce and cheese will help protect the bottom bun from getting too soggy from the sauce.
Stack on the sliced roast beef.
Add an optional micro greens. You can use any breed of micro greens.
Place on the sliced radishes and onions.
Lastly, place on the sliced tomatoes and then the top bun. Serve.
Notes
Make-Ahead: If all the ingredients are kept separate, you can prepare this roast beef sandwich recipe up to 2 days ahead of time.How to Store: Store the toppings, bread, horseradish cream spread, and buns separately covered in plastic wrap for up to 1 week in the refrigerator. These ingredients, unfortunately, will not freeze well.Other kinds of cheese that go great with roast beef are, blue cheese, cheddar, asiago, gouda, fontina, or Swiss. However, you don’t even need to use cheese for this sandwich.There are several brands of roast beef to choose from including but not limited to, Greenridge Farm, Boar's Head, Dietz and Watson, or Applegate.If you are looking to do it yourself and want something that stands out, try slicing it from my Smoked Prime Rib recipe.There are many options for toppings on this sandwich. Most of these choices will depend on your preferences. If you consider all the things beef goes well with, it will make your options that much better.You can use white, sweet, or yellow onions in place of the red onions I used.Feel free to use Roma tomatoes instead of heirlooms.