Somerset Onion Tarte Tatin with Aged Cheddar

⏱ 75 min · Serves 4

Sticky cider-caramelised onions turned out over crisp puff pastry, with sharp aged cheddar melting into the folds and a scatter of thyme. Sweet, savoury and properly West Country — it looks far harder than it is.

Per serving: 640 kcal · 15.0g protein · 54.0g carbs · 40.0g fat

Ingredients

• 6 medium red onions (about 900g), peeled
• 40g butter
• 1 tbsp olive oil
• 2 tbsp light brown sugar
• 2 tbsp cider vinegar
• 150ml dry cider
• 4 sprigs fresh thyme, plus extra to serve
• 1 tsp Dijon mustard
• 320g all-butter puff pastry sheet
• 100g aged cheddar, coarsely grated
• Sea salt and black pepper
• Handful of watercress, to serve

Method

1. Heat the oven to 200C/180C fan/gas 6. Trim the root ends of the onions but keep them intact, then halve each one through the root.
2. Melt the butter with the oil in a 24cm ovenproof frying pan over medium heat. Lay the onions cut-side down in a snug single layer and season well. Cook undisturbed for 8-10 minutes until deeply golden underneath.
3. Scatter over the sugar and let it melt and bubble for 2 minutes, then pour in the cider vinegar and cider. Tuck in the thyme sprigs, cover loosely with foil and simmer gently for 15 minutes until the onions are tender.
4. Remove the foil and let the liquid reduce for 5-8 minutes to a glossy, syrupy caramel that coats the onions. Stir the Dijon into the syrup around the onions. Make sure every onion half is cut-side down and neatly packed. Remove from the heat and cool for 5 minutes.
5. Scatter half the cheddar over the onions. Unroll the pastry and cut a circle slightly larger than the pan. Lay it over the top and tuck the edges down inside the pan with a spoon handle. Prick a few steam holes.
6. Bake for 25-30 minutes until the pastry is puffed, deep golden and crisp.
7. Rest for 5 minutes, then run a knife round the edge, place a large plate over the pan and confidently invert. Rearrange any stray onions.
8. Scatter with the remaining cheddar so it softens in the heat, add fresh thyme leaves and black pepper, and serve in wedges with dressed watercress.