Butternut squash and cavolo nero gratin

Matt Tebbutt’s butternut squash and cavolo nero gratin is a comforting autumn classic with real restaurant polish. Sweet roasted squash and deep-green cavolo nero bake in a rich, mustard-spiked Parmesan custard until silky and just set. A warm salad of charred broccoli, pears and toasted almonds with a lemon and honey dressing brings bright, fresh contrast to every indulgent spoonful.

The squash, cavolo nero, broccoli, pears and almonds bring fibre, vitamins and healthy fats, though the double cream and Parmesan in the rich custard nudge it up a notch on saturated fat. Swap in vegetarian hard cheese and lighter cream if you fancy.

Estimated nutrition per serving (approx., based on 6): 640 kcal | Fat 48g | Carbs 32g | Sugars 14g | Fibre 6g | Protein 19g

Method

Get Ready (5 minutes)

1. Preheat the oven to 220C/200C Fan/Gas 7. Getting the oven nice and hot from the start is key here – it gives the squash those lovely caramelised edges rather than just steaming it soft.

Roast the Squash and Blanch the Greens (25–30 minutes)

2. Toss the squash with flavour. Pop the butternut squash rounds into a large mixing bowl with a generous drizzle of olive oil, the thyme and the chopped garlic. Season well with salt and pepper, then get your hands in and toss everything until every round is glossy and coated. Trust me, hands work better than a spoon for this job.
3. Roast the squash by spreading it out in a single layer over a large baking tray. Give each piece a little breathing room – crowded squash steams instead of roasting. Bake for 25–30 minutes, until soft and lightly golden. You can do this a few hours ahead if you like; it reheats happily.
4. Blanch the cavolo nero while the squash roasts. Bring a large saucepan of well-salted water to the boil, add the cavolo nero and cook for just 1–2 minutes until tender. That short blanch keeps the gorgeous deep-green colour and tames any bitterness. Drain well and set aside.

Make the Custard and Assemble (10 minutes, overlaps with the roasting)

5. Reduce the oven temperature to 170C/150C Fan/Gas 3½. A gentler heat now means the custard bakes slowly and evenly without curdling – low and slow is the secret to that silky texture.
6. Mix the custard. In a large bowl, whisk together the beaten eggs, double cream, mustard, milk, grated Parmesan, nutmeg and chives. Season with salt and pepper and give it a final whisk. It should smell properly savoury and inviting at this stage – that’s exactly what you want.
7. Layer the gratin. Arrange the roasted squash and blanched cavolo nero in your gratin dish, alternating them so every slice gets a bit of both. Pour the custard mixture evenly over the top, letting it seep into all the gaps between the layers.

Bake and Rest (60–65 minutes, plus 15 minutes resting)

8. Bake until just set. Slide the dish into the oven and bake for 45–50 minutes, until the custard is just set with a slight wobble in the middle – like a good cheesecake, that wobble means perfection. Then let it rest for 15 minutes before serving; this helps it firm up and slice neatly. Grate over a little extra Parmesan just before it goes to the table.

Roast the Broccoli and Toast the Almonds (15 minutes, during the gratin’s rest)

9. Preheat the oven back up to 220C/200C Fan/Gas 7. Clever timing here – the salad comes together while the gratin rests, so everything arrives at the table warm and ready.
10. Roast the broccoli. Spread the Tenderstem broccoli over a large baking tray, drizzle with 1 tablespoon of the olive oil, and season with salt and plenty of black pepper. Roast for 12–15 minutes, turning halfway through, until tender and charred at the edges. Those charred bits are pure flavour, so don’t shy away from a little blackening.
11. Toast the almonds. Meanwhile, tip the almonds into a dry frying pan over a medium heat and toast for 3–4 minutes, tossing regularly, until golden and smelling wonderfully nutty. Keep an eye on them – they go from golden to burnt quickly. Roughly chop and set aside.

Dress and Toss the Salad (5 minutes)

12. Whisk the dressing. Combine the lemon zest and juice, mustard, honey and remaining 3 tablespoons of olive oil in a small bowl. Whisk with a whisk until glossy and emulsified, then season with salt and plenty of black pepper. Taste it – it should be bright, sweet and punchy all at once.
13. Prep the pears. Quarter and core the pears, then cut them into thin wedges. Leaving the skin on adds colour and helps them hold their shape in the warm salad.

Serve (2 minutes)

14. Toss the salad. Put the warm roasted broccoli in a large serving bowl and add the pear wedges, spring onions, parsley and mint. Pour over the dressing and gently toss with your hands or a couple of spoons – gently is the word, so the pears stay pretty.
15. Finish and serve. Scatter over the toasted almonds and shave the Parmesan generously over the top. Serve the salad warm or at room temperature alongside the rested gratin, and watch it disappear.

Additional Notes

• Assemble the gratin up to the baking stage earlier in the day, then bake when you’re ready – perfect for entertaining.
• Leftover gratin keeps well in the fridge for up to 3 days and reheats beautifully in a moderate oven.
• Squeeze a little lemon over the cut pears if prepping ahead, to stop them browning.
• For a fully vegetarian dish, always choose a vegetarian hard cheese in place of traditional Parmesan.