Carbonnade is a hearty Flemish recipe, just right for cold winds and wet weather. The name comes from charbon, or “charcoal,” and this dish was once a grilled steak flavored with mustard. More to my taste is this version stewed in the oven with beer, then topped with mustard-flavored croûtes. I like to pick up color by serving it with braised red cabbage. Northerners prefer their mustard feisty, so hot rather than milder Dijon mustard is correct here.