2) Tuna tacos
Pan-sear a tuna steak (RARE is best!), I season a bit but not heavily.
Slice it into long thin strips.
Make tacos with spinach, any other veggies you want, a bit of cheese, and homemade guacamole.
Just don't eat five of them, and it's a great meal. As always, serve with veggies. I find that this pairs well with a side of "fajita topping" veggies.. onions, bell peppers etc.