Dippers can't help themselves: To them, a sandwich always tastes better dunked, be it in a bowl of hot soup, a puddle of salsa or a smear of ketchup on their plate. Miss Manners might not approve, but they go on dipping just the same.
When roast beef leftovers are in your fridge, you'd be wise to join them.
French dip sandwiches, the lunch-counter favorite, originated in Los Angeles nearly a century ago (the name comes from the French roll it's served on). The idea is simple: Stuff a crusty roll with sliced roast beef or beef brisket and serve it "au jus," literally, doused with hot pan juices.
At the two landmark restaurants that claim to have invented it, Philippe the Original and Cole's P.E. Buffet, a French dip comes "wet," meaning the roll is dipped in hot pan juices before the sandwich is assembled. Almost everywhere else it's served dry with a cup of hot beef broth, so you can happily dunk your own as you nibble away.
Regardless of how you choose to serve it at home, a French dip is only as good as the components that go into it. Here's our advice for getting it right.
The meat
The better the beef, the better your sandwich. If you're serving rib-eye roast or tenderloin, all you need to remember the day after is to slice it thinly when it's cold and trim off as much fat as possible. A handy substitute is roast beef from a deli, but make sure to buy top quality, and taste it before plunking down your money.
The roll
