Put a 28cm non-stick frying pan on a medium heat with 1 tablespoon of oil and the butter (or, even better, any leftover dripping you have in the fridge). Pick in the fresh herb leaves and let them crisp up for a minute, then add the potatoes, veg, and any leftover chestnuts you’ve got. There’s no need to chop anything first, as now we’re going to mash it all up with a potato masher into a nice, flat, even layer. Season well with sea salt and black pepper, and cook for 3 to 4 minutes, or until a lovely golden crust starts forming on the bottom. Now we get into the rhythm of the secret to good bubble & squeak. Use a fish slice to fold those lovely crispy bits back into the mash, then pat and flatten everything down again. Let it crisp up again, then repeat the process, and – importantly – keep repeating it over a period of about 20 minutes, until it’s golden, super- crispy and delicious. About halfway through, nick a bit, taste it, and correct the seasoning if you need to. When it’s looking good, you can serve it right away, or you can leave it on the lowest heat for a while – the flavour will only improve. You can serve this any which way you like – let’s be honest, it’s going to be amazing whatever you have it with. I like mine with fried eggs, a little lemon-dressed watercress and a few bombs of Piccalilli. Slices of leftover cooked ham are always going to go down a treat, too.