Tomato, olive and leek bake

Heat 2 tbsp oil in a large ovenproof frying pan or shallow casserole dish. Tip the leeks, tomatoes, thyme, garlic and 1 tbsp water into the pan and fry until the leeks are soft and the tomatoes have started to break down (about 18 minutes).

Meanwhile, put the cannellini beans and their liquid into a high-speed blender with the nutritional yeast; season. Whizz until smooth, then tip into the pan with the veg. Add the olives, stir to combine and bring to a simmer. Cook until slightly thickened (about 2 minutes).

Preheat the grill to medium-high. In a bowl, combine the bread, walnuts, remaining 2 tbsp oil and a pinch of salt. Take the veg off the heat and scatter the bread mixture on top, along with some extra thyme leaves. Grill for 4-5 minutes until golden brown and bubbling.