Stuffed Baked Zucchini

I usually use the word 'courgette' (finding certain celebrity chefs obsession with Italian cuisine a bit tiresome), but as this is a recipe from my Italian penpal Gio, it seems appropriate to go with zucchini for once.
This recipe uses round courgettes - gah - zucchini, though you can get away with using the long varieties too.

Gio's Stuffed Baked Courgettes
4 zucchini or summer squash
1 tbs olive oil
1 onion, chopped
4 tomatoes, peeled, deseeded & chopped (or 1 cup of passata or leftover tomato sauce)
1 cup cooked rice (or spelt, wheat berries or a blend of grains)
1/2 tsp sweet paprika
salt & pepper

Preheat the oven 200C/400F/G6. Halve the courgettes & scoop out the centers. Chop them coarsely & set to one side. Place the courgette halves on a baking tray & cook for 10 minutes. While the courgettes are cooking, fry the onion in the olive oil in a pan. Add the chopped courgette flesh & tomato & cook for about 5 minutes. Add the rice & stir until warmed through. Add the paprika & season. Fill the courgettes with the mixture, and return to the oven for 20 minutes.
Serve with salad or as a side.

This is a really good way of using up leftover pilau, Mexican rice, paella, risotto or any other grainy dish.
Om nom nom!