Heat your oven to 200°C/Fan 180°C/Gas 6. Peel your butternut squash. Cut it in half lengthways, scooping out the seeds with a spoon. Cut the squash into 2 cm cubes. Wrap the garlic in a square of foil to make a parcel.
Chuck the squash cubes onto a baking tray. Drizzle over ½ tbsp oil and the red wine vinegar. Add the parcel of garlic. Roast for 20 mins in the oven. Crumble the stock cube into a heatproof jug. Pour over 200 ml boiling water. Swirl to dissolve.
Meanwhile, peel and thinly slice the onions. Heat 1 tbsp oil in a heavy based pan. Cook for 15 mins on a low heat till translucent. Finely chop the rosemary leaves and add half to the onions. Cook for a further 5 mins.
After the squash has cooked for 20 mins, remove the garlic. Place the lamb chops on top of the squash, scatter over the remaining rosemary and season. Put back into the oven to cook for 20 mins.
Tip the flour into the onion pan and stir to coat. Cook for 2 mins. Add the stock and milk, beating out any lumps. Squeeze the garlic from their skins and mash with the back of a knife. Stir into the onions. Cook on a low heat for 10 mins, stirring regularly.
Tear the kale into bite sized pieces, removing the tough stem and ribs. Finely chop the chilli, discarding the seeds and white bits. Drain and rinse half the tin of butter beans.
Add the kale, chilli and butter beans to the creamy onion sauce. Stir well and cook for 10 mins till the kale is wilted. Remove the squash and lamb from the oven. Divide between two plates and serve with a spoonful of the creamy kale and butter beans.