I have never liked French Dip because of the soggy bread so I came up with something that I like instead.
Roast Beef (I go to the Deli for it)
Cheese (any kind you like)
Onion Soup Mix
Pu the roast beef, peppers, onions, and cheese on the hoagie bun. Then broil it until the cheese is melted and the bread is toasted. Mix sour cream and onion soup mix together, spread on the bread. I don't have measurements, just do what looks good. It is yummy, easy, and fast. Ella doesn't like the peppers and onions, so I just do meat and cheese for her.