Marcus Wareing serves his smoky-sweet barbecued steak in a crunchy baguette, with a homemade herb sauce for company. For this recipe you will need a food processor and a barbecue or large griddle pan.

It's hard to go wrong with a steak sandwich in its most basic form. Savory, juicy steak on a baguette or sandwich roll is a meal for the ages. However, unconventional toppings (move over onions ...