If you want to get ahead, both the chive cream and butter can be made the day before, leaving you just the sweet potatoes to grill on the day.
For the sweet potatoes
1kg sweet potatoes, unpeeled, cut in half lengthways, then each half cut at an angle into quarters
3 tbsp olive oil
For the chive soured cream
300g soured cream
1½ tsp lime juice
For the hot sauce butter
100g unsalted butter
3 small garlic cloves, peeled and finely chopped
½ tbsp tomato paste
½ tsp cinnamon
80ml hot sauce of your choice – I like Cholula
30ml maple syrup
1½ tbsp lime juice
30g pumpkin seeds, toasted and lightly crushed in a mortar
1 lime, cut into quarters
5g chives, cut into ½cm lengths
1. Put two litres of water in a large saucepan, add three tablespoons of salt and bring to a boil. Add the sweet potatoes, turn down the heat to medium-high and leave to simmer for 20-25 minutes, until tender – a small, sharp knife should go through easily, but you don’t want them mushy or breaking apart. Drain, transfer to a large bowl, add the olive oil and toss gently with your hands so the sweet potatoes are well coated but still hold their shape.
2. Now make the chive soured cream. Put 100g soured cream in the small bowl of a food processor, add the chives, lime juice and half a teaspoon of salt, and blitz smooth. Pour into a bowl, fold in the remaining 200g soured cream and refrigerate until it’s time to serve.
3. For the hot sauce butter, put the butter, garlic and tomato paste in a small saucepan set over a medium heat and leave to cook for five minutes, until the garlic is fragrant and the butter bubbling. Take off the heat, stir in the cinnamon until the mixture is smooth, then stir in the hot sauce, maple syrup, lime juice and half a teaspoon of salt, and set aside.
4. Put a griddle pan on a medium-high heat and, once it’s really hot, grill the sweet potatoes in batches for two to three minutes on each side, including the skin, until dark grill marks appear. Transfer to a large bowl and repeat with the remaining sweet potatoes.
5. Return the butter to a low heat, until gently bubbling, pour over the sweet potatoes and toss gently to coat.
6. To assemble the dish, spoon half the chive soured cream on to a large platter with a lip. Arrange the sweet potatoes on top, then generously spoon over the hot sauce butter. Sprinkle over a quarter of the pumpkin seeds and the chopped chives, and serve warm with the remaining soured cream, pumpkin seeds and lime wedges on the side for everyone to help themselves.