40g essential reduced fat soured cream(Available in selected stores)
Preheat the oven to 220˚C, gas mark 7. Put the lamb steaks in a bowl and rub with 1 tsp harissa and the crushed garlic; season and set aside. Combine the chopped shallots and lemon juice in a small bowl and leave to steep.
In a roasting dish, toss together the peppers, tomatoes and unpeeled garlic cloves with the oil and remaining 2 tsp harissa; season. Roast for 15 minutes, then add the butter beans and cook for a further 20 minutes. Once you’ve added the butter beans to the vegetables, put a griddle pan over a high heat. When the pan is hot, add the lamb steaks and cook for 5-7 minutes on each side, then transfer to a board for 5 minutes to rest.
When ready to serve, squeeze the roasted garlic cloves out of their skins and mash into the roasting tin. Stir in the steeped shallots and their liquid, the lemon zest and coriander. Remove half of this veg mixture and chill it for tomorrow. Divide the rest between 2 plates. Slice the lamb steaks and arrange on the vegetables. Serve with the soured cream on the side.