Warm the oil in a large non-stick pan.

Add the onion and garlic and sweat over a medium heat until translucent.

Add the courgettes and fry for another minute, then add the peppers and fry until everything is soft.

Add the tomatoes then shred half of the basil and add to the pot with the bay leaves.

Bring up to a simmer, then leave bubbling away for about 20 minutes, stirring occasionally until it has reduced, then turn off the heat, season to taste and set aside.

Put the milk, flour and butter in a non-stick pan and whisk over a high heat until it begins to thicken. Add the sage with a good pinch of salt and pepper and keeping whisking gently until it's nice and thick. Take off the heat.

Peel the potatoes, cutting the larger ones in half, cover with freshly boiled water and boil on the stove for 3-5 minutes until just becoming tender.

Drain and leave until cook enough to handle, then cut into thin 2-3mm slices.

To assemble the lasagne, grease a large lasagne tray or casserole dish with a little spray oil. Spread a thin layer of the tomato sauce, then cover with a single, slightly overlapping layer of potato, followed by a layer of the white sauce, then another potato layer. Repeat until you finish with a white sauce topped layer.

Sprinkle the cheese on top of the lasagne, followed by a good dredge of pepper.

Push a sharp knife into the centre of your lasagne to make sure the potatoes are cooked through, sprinkle with the remaining basil leaves, then you're ready to serve.