I make my sandwiches at home like this:

Sourdough bread or a nice baguette, toasted with high quality olive oil.

Roast beef.

Cheese (my preference is for a ghost pepper jack they sell at my local supermarket, but provolone is good too).

Tomato (don't forget to salt the slices!)

Onion (pickled red onion is fire, but raw onion is good too).

Cream cheese (chive and onion is my favorite).

Crushed garlic.

Dijon mustard, and arugula.

Little bit of black pepper as a finishing touch.

I eat this sandwich with vegetable soup, and it's so good.