Lily Higgins: Butternut, apple & thyme gratin

Preheat the oven to 220C.

Mix the garlic with the milk and stock.

Peel the squash then cut in half and scoop out the seeds, slice thinly. Use a mandolin or food processor if you have one. Halve and slice the onions thinly too. Place in a large mixing bowl. Peel and thinly slice the apples. Add the apple to the squash. Season with salt and pepper and mix everything together gently. Place half the slices into a large buttered oven-proof dish. Pour over half the stock mix. Scatter with half the thyme. Top with the remaining slices and pour over the stock.

Cover the dish with foil and bake for 40 minutes. Remove the foil and bake for a further 15 to 20 minutes, scattering over the remaining thyme for the final five minutes. Leave to rest for five minutes before serving.