If you like tuna, I make what I consider really 'posh' tuna sandwiches:
French stick type crusty bread, split in two
Spread both sides of the bread with black olive tapenade (or you can get a jar of kalamata olives & smoosh them up, if you can't find tapenade)
Mix the (white, albacore, drained) tuna with salt, pepper, Hellmans mayo (easy on the mayo) & squeeze of lemon
Spread the tuna stuff on the bread
Then add sliced ripe tomatoes (if you like tomatoes, I don't!), thinly sliced red onion & salad, maybe some cucumbers?
Wrap them up tightly in foil.
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(It's fancy tuna mayo, but the tapenade, the squeeze of lemon, red onion, etc give it a little extra something!)