Mix Aioli ingredients and set aside.
Simmer the potatoes in lightly salted water for 15 minutes, or until tender. Drain and mash thoroughly. Beat in the butter and egg yolk then finally the cheese and season with potato seasoning. Cover and leave until firm and cool enough to handle.
Shape the mixture into 10–12 croquettes.
Put the flour, whole eggs, and breadcrumbs into three separate shallow bowls and beat the eggs. Dip each croquette in the flour, then coat in the egg before dipping in the breadcrumbs. Transfer to a baking tray, then preheat the oven to 180C.
Drizzle the croquettes with oil and bake for 20 minutes, or alternatively use the fryer.
Serve with mustard aioli and rocket salad leaves.