Chicken With Parmesan, Garlic, and Herb Crust

garlic clove, peeled

fresh flat-leaf parsley leaves

slices whole-wheat bread

grated Parmesan (1 ounce)

olive oil

kosher salt

freshly ground black pepper

skinless, boneless chicken-breast halves, 2 pork tenderloins, halved (1 1/2 to 2 pounds total), or 1 1/2 pounds skinless salmon fillet (4 pieces)

Dijon mustard