Take 100-150g of Mexican beans and put them into a tall bowl, add a spoonful of extra virgin olive oil, the egg yolk and blend to a smooth cream with a stick blender.
Take the monkfish fillet, clean, bone thoroughly, glaze with the creamed beans and put into the oven, preheated to 150°C, for 20 minutes.
Cut the Fontina into cubes, add the remaining beans, salt to taste and add a little chopped mint.
Pour the creamed beans into parchment-lined round moulds, not too tall, and bake at 180°C for ten minutes.
Slice the potatoes and leeks into rounds and boil in salted water until cooked. Whizz to a velvety consistency with a stick blender.
To serve, pour some leek cream in the centre of the plate and add the bean flan.
Finely slice the fish and arrange around the flan in a petal pattern.
Finish the plate with a teaspoonful of salmon roe on the flan, a drizzle of extra virgin olive oil, some fresh mint leaves and a good twist of white pepper.