Somewhere between 125g and 250g spagettie broken into half and in half again - I eatalot 
1 PKT Mushroom cuppa-soup
1 tin shredded tuna in brine (not oil) OK so that’s the heavy bit & the tin to pack out…
Make up soup, but keep it on the thick side (use a bit less water)
Boil up spaggettie, Spice to your liking… I use salt & garlic powder (only a little, I’ve got to live with myself) when cooked pour water off, add soup as a sauce, mix through, add tuna, mix in
Add other stuff like raw fine chopped onion… if you like…