To make the Mornay sauce: melt the butter and add the flour. Cook on a low heat then add the cold milk and bring to the boil. Take off the heat, add the egg yolks and the grated Ossau-Iraty. Mix well, spice and season, pour onto a tray until 4cm thick, then leave to set in the freezer.
To make the batter: mix the whole eggs and olive oil and season. Put to one side. Mix the parsley in a blender. Add 400g of the breadcrumbs and the lemon zest. Mix until the breadcrumbs turn green.
Put the chorizo slices onto a tray and cook in the oven at 100°C for about 40 minutes, turn them over half way through the cooking time. Keep them at room temperature.
To make the Ossau-Iraty fritters: take out the Mornay sauce and cut out 4 rectangles of about 5 x 2cm. Dip these rectangles in the batter and cover both sides then coat with the remaining breadcrumbs. Repeat these steps to create a thick crust. Fry the fritters.
Cut the fritters in four and place them in a plate. Add the fresh herbs. Add the dried chorizo slices, then garnish with some of the black cherry jam.