Spaghetti with tuna, spinach and lemon

Actually, this may not have been spinach - it might have been chard. It's grown some rather enormous leaves on the allotment, anyway, which the snails have started to take a liking to. So we thought we should get in first.

You'll need:

enough spaghetti for three (a small handful per person - spaghetti always miraculously expands when cooked)
1 large onion, finely sliced
1 clove of garlic, finely chopped
unidentified green leaves - preferably spinach/chard or that sort of thing, sliced into strips
1 tin of tuna
lemon zest (about half a lemon will do)
lots of black pepper

Stick the spaghetti into a large pan of boiling water - it'll need 7-8 minutes until it's al dente.

In the meantime, fry the onion and garlic in a good slug of olive oil, until they've softened. Add the greens, and fry for a couple of minutes until they've wilted. Stir in the tuna, and leave to warm through.

Drain the spaghetti, and tip into the greens/tuna pan. Stir everything thoroughly, so the spaghetti becomes covered with the tuna and onions. Season well with lots of black pepper, and some grated lemon zest.

Divide up into bowls, and top with a little extra drizzle of olive oil, and maybe some parmesan cheese.