Trim and halve the brussels sprouts, then place on a large baking tray. Add the oil, grate over the lemon zest, then sprinkle with the chilli flakes, sumac and a pinch of sea salt and black pepper. Mix with your clean hands to coat.
Roast in the oven for 10 minutes – the sprouts should start to caramelise in places; when that happens, scatter over the Summerfields Alpine cheese and roast for a further 15 minutes, until the cheese is crisp and golden brown, and the sprouts tender.