Heat the butter in a frying pan over medium heat. Lightly bash the garlic using the side of your knife and add to the pan along with the white parts of the spring onions. Stir to coat in the butter and fry for 3-4 mins. Stir in the miso and beans along with 200ml water. Bring to a simmer and cook for a further 4-5 mins.

Remove the garlic cloves and, using the back of a wooden spoon, lightly press some of the beans against the side of the pan to mash them slightly. Stir in half the green tops of the spring onions and season with salt, pepper and the lemon juice.

Spoon the beans over the toast. Drizzle over the chilli oil, if using, and garnish with the remaining green spring onion tops to serve.