Tuna pasta.
This is the one dish that is a staple at our house (amid the profusion of improvised soups), mostly because the Brit grew up eating it and is always satiated by it. And it's a combination of things I wouldn't have imagined or come up with on my own, but I totally dig this dish too.

Tuna Pasta
Olive oil
Medium onion, diced
3 big cloves of garlic, minced or pressed
1 tsp dried basil
1/2 tsp dried oregano
A few shakes of red pepper flakes
1/2 tsp of fennel seeds (if you have them)
Two cans of tuna
A big can of diced tomatoes and their juice
A medium sliced zucchini
A chopped red, yellow, or orange bell pepper
Half a bag of fresh spinach
Chopped kalamata olives
Feta cheese
A box of penne, farfalle, or any short cut of pasta

Put a pot of water on to boil.

Saute the onions, garlic, and herbs in olive oil until the onions are translucent. Add the tuna (drain the water into your cat's dish) and cook a bit longer, stirring to break up the tuna. Pour in the entire can of tomatoes and cook down for a bit. Add zucchini and bell peppers and simmer for a few minutes, until the vegetables are tender but not overcooked. Dump in the spinach and stir to wilt, and turn the heat wayyyy down. Sauce will be very thick and chunky.

Once your pasta's done, top with sauce, olives, and feta to taste.

You can make all kinds of modifications to this recipe depending on the vegetables you have handy, but I think zucchini and spinach are the most solid choice. Bonus: the leftover sauce makes amazing tuna melts, if you have a really crusty bread and some schmancy cheese.