Rocket pesto bean burgers

My (fantastic) local pub does a pretty good vegan bean burger. It's a rich thing, hefty on the cumin and sweet potato, and they serve it with a little avocado.  A good time. I have, however, taken to polluting its vegan essence by ordering it with a slab of cheese on top. This is, if anything, an even better time. But you have to pick your cheeses.Sharp cheddar on a bean burger, maybe even Red Leicester or a Wensleydale? Yup, for sure. Mozzarella? Not so much.It ought to work, but the thick, gentle creaminess of the mozzarella just fights the cumin and the spicy/sweet of the dark beans and sweet potato. Hmm. What to do? Could I hack together a bean burger that would be a bit lighter and fit nicely with some melty-gooey cheese?The short answer is "kind of", and the long answer is this week's experimental recipe.

Ingredients:

• Cannellini beans, 1 can (about 250g drained weight)
• Potatoes, 150g (1 medium)
• Onion, 1 small
• Garlic, 2-3 cloves
• Pine nuts, 50g
• Rocket 75g
• Pecorino, 15-20g
• Fresh basil, a small bunch - say 15g
• Olive oil, about 1tbsp
• Lemon, 1
• Plenty of black pepper
• Semolina or breadcrumbs for dusting
• Optional: 1 egg

Makes 2 large patties, or 3 small ones.

Instructions:

Rinse the beans and drain them well. Grate the cheese, peel the garlic, and zest half the lemon.Peel and roughly cube the potato, and boil it until thoroughly tender (6-7 mins). Drain well, and leave to the side to dry out a little and cool.In a frying pan on a fairly high heat, quickly toast the pine nuts, tossing occasionally until they just colour. Put to one side.Finely dice the onion, and fry it on a low heat in a little oil for 8-10 mins, until soft and just colouring.Once the potato is cool, mash it thoroughly with most of the beans (hold a handful back), to form a smooth mix. Add the onion, and the rest of the beans, and mash them in roughly.Put the rocket, basil, olive oil, garlic, grated pecorino, and 30g of the pine nuts in blender with a little salt, and a small squeeze of juice from the lemon. Blitz it all to form a rough, thick pesto. Mix this into the bean mixture, along with the lemon zest, reserved pine nuts, and the egg if you're using it (see later). Put it all in the fridge for a bit to cool down and firm up.Shape the mix into patties, dust them in semolina or breadcrumbs, and fry on a medium heat for 6-8 minutes on each side until they've browned a bit and heated through. You might want to finish them off in a medium oven (say, 160c) with thick slices of mozzarella on top, if you want it gooey-melty. 10-15 mins should do nicely, perhaps with a flash under the grill at the end to bubble it all up.Note that the burgers will probably fall apart. That's what the egg is for. I didn't use it, and mine had some (but not fantastic) structural integrity. They held together with very careful handling, and collapsed at the first bite. An egg ought to provide a bit more binding, but I've not tried it yet.What you get is some earthiness from the beans, shored up by the nutty peppery hit from the pesto, and all lightened out a bit by the basil and the zest. They come up a lovely green colour, too, which you can't really see in the pictures because reasons*

They're still a little heavier than I'd like, but make a nice alternative if you want a bean burger with a gentler, more Italian-y flavour. Or, as in my case, a thin pretext to guzzle mozzarella while looking like you're having an actual meal that might be prepared by a responsible human adult.*I forgot to buy mozzarella and buns for batch two, so the pictures are from the initial, less herby test batch.