Slow-cooked borlotti with garlic, tomato and sage

I used to cook borlotti with water and herbs on the stove but Steve, who works in our kitchen, showed us how to cook them this way. This is far better: the borlotti absorb the oil and have a really beautiful flavour.

500g/1lb fresh borlotti, shelled
100ml/31/2fl oz extra-virgin olive oil
Water to cover
1 bulb garlic, cut in half
2 ripe tomatoes, roughly chopped
1 small bunch sage
A good pinch of sea-salt

Heat the oven to 190C/375F/Gas5. Place the borlotti in a baking dish. Drizzle over the olive oil and pour over the water to cover. Add the garlic, tomatoes and sage, sprinkle over the salt, cover with foil and place in the oven. Cook for 45 minutes or until the beans are tender to the bite. These are delicious with grilled lamb or white fish such as turbot.