Place a large saucepan with a drizzle of oil over medium heat, add half of the butter and let it melt. Stir the onions and 15g of thyme leaves along with a good pinch of salt. Cook the onions, stirring occasionally until they have softened and lost a lot of liquid. After about 25-30 mins they should be golden and very soft. Add a splash of the beef stock if the onions are catching on the bottom of the pan.

Meanwhile, heat a small frying pan over a medium heat and add a drizzle of olive oil. Add the breadcrumbs, the remaining thyme leaves and plenty of fresh cracked black pepper, cook until golden brown. Transfer to a bowl, season with salt and let cool down.

Once the onions are caramelised, reserve ¼ on the side. Add the garlic into the saucepan and cook for 2 mins.

Stir in the white wine and let it fully evaporate. Add the remaining beef stock and let it reduce until the onions are jammy and the stock has reduced by ⅔, around 10-15 mins.

Meanwhile, cook your pasta in boiling salted water for 1 min under al dente. Once your pasta is done, add it to the caramelised onions, making sure to reserve the pasta water.

Toss the pasta into the sauce, with the remaining butter. Use the pasta water to thin the sauce out. Season with salt and plenty of pepper.

Remove the pasta from the heat and vigorously stir through half of the cheese until emulsified. Squeeze in some lemon juice. Taste and season with salt and more freshly cracked pepper, if desired.

Stir the lemon zest and remaining cheese into the breadcrumbs. Serve the pasta with some of the reserved caramelised onion and Gruyère and thyme breadcrumbs on top. Enjoy!