Put 25ml of olive oil into a large pan on a medium heat. Add the onions, a pinch of salt (this helps the onions to lose water and therefore cook more quickly) and the bay leaves. Cook, stirring occasionally, until the onions are about three-quarters of the way to being caramelized: they should be light golden brown but translucent. The time the onions take to cook will depend on the size of the pan used.
Add the wine and cook to evaporate the alcohol, then add the stock and reduce by about half, just so everything comes together – you’re looking for a nice sauce-y spoonful.
Put the remaining 50ml of olive oil into another pan on a medium-high heat, and add the squid. Season with salt and pepper, and cook for 1–1½ minutes on each side – the tentacles might only need a minute.
Remove the squid to a chopping board and cut into three or four 2–3cm rings. Add to the pan of caramelized onions, mixing together, and cook for a couple of minutes more on a very low heat, just to bring it together. Finish with chopped chives, and serve.