Start by softening the onions in a little olive oil. Season generously with Maldon salt and cook on a low heat until they are lovely and caramelised. Low and slow is the key and it will take about 20 mins so be patient - I promise it’s worth it!

Meanwhile brown the butter in a pan on a medium heat. It will go from melted, to very loud and bubbly and then quiet and foamy. Keep stirring until it turns a light amber colour and smells of roasting chestnuts. Brown butter is lovely, burnt butter not so much - so don’t let it burn and pour it into a heatproof bowl once golden to stop the cooking process.

Cook the pasta in salted boiling water

In a bowl mix together the egg yolks, Parmesan and lemon juice and then season well with black pepper. Add a little of the hot pasta cooking water to this mixture to temper it. Stir well.

Add the brown butter, caramelised onions and a splash of pasta cooking water to a blender and blitz until lovely and creamy.

Tip the sauce into the cooked pasta. Add the egg mixture. Stir and toss through adding a little more pasta water to loosen if needed. Taste. Adjust seasoning as needed and top with more parmesan. Enjoy!