In a medium saucepan heat up 1 tablespoon of oil, add the bay leaf, garlic and onion and cook on a low heat for 3-4 minutes, stirring occasionally. Add the tomatoes, tomato puree, brine from 1 tuna tin, season to taste, cover and simmer for 7 minutes.
In the meantime in a large non-stick pan heat up 1 tablespoon of oil and fry the squash cubes on a high heat for about 7-8 minutes stirring often until softened and lightly browned. Remove from the heat and place in your oven dish.
In the same frying pan heat up the spinach and cook over a fairly high heat until reduced in size, for about 1 minute, stirring all the time. Stir the spinach mixture into the tomato sauce. Adjust the seasoning if necessary.
Spread the tuna over the squash, pour the sauce over the whole thing, top with feta, drizzle with a little oil, sprinkle some paprika and bake in the centre of the oven for 30 minutes. If the feta starts to brown too much cover loosely after 20 minutes.
Remove from the oven and serve. Garnish with parsley and enjoy with pasta, quinoa, potatoes, couscous, crusty bread or simply on its own.
Use tuna in water rather than oil (you will need to use some of the tuna water in the recipe).
The spinach needs to be fried very briefly. Once it wilts down it is ready to combine with the sauce.