DO-AHEAD TIP: Marinate pork cutlets for 30 minutes (see recipe).
Preheat grill to MEDIUM.
In a shallow bowl, whisk together first 6 ingredients (mustard through black pepper) until well blended; reserve a few tablespoons for basting.
Rub remaining marinade into the cutlets and place them in a shallow dish; cover with plastic wrap and refrigerate for 30 minutes.
Lightly oil the grill grate; grill cutlets over indirect heat for 15 to 20 minutes, turning occasionally and basting with reserved marinade, until cooked through. Watch carefully to prevent burning!