I'm going to make a wild assumption that you all know how to make a hero sandwich. Having established that, I'm just going to put out some ideas to give it a little Diva. That means make it special without spending a lot.

Make it Grand. Use a full loaf of bakery bread (day old is fine) sliced lengthwise to make one huge sandwich. For a picnic it's easier if you slice it in portions at home. If you use toothpicks to secure the sandwich be sure they're highly visible. Nothing ruins a picnic faster that a perforated trachea. Straws are a safer option.
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