Mix the cubed potatoes with the seasonings and pop them in the air fryer/oven for approximately 20 minutes on 220°C fan/200° air fryer.
Meanwhile to make the béchamel, melt the butter and then add in the flour. Cook this out for a few minutes and then slowly add in the milk, bit by bit, stirring constantly until you get a thick sauce.
Then add in the mustard and the cheddar and season to taste.
Top the bolognese with the cooked potatoes and cheese sauce, sprinkle with the remaining cheese and pop under the grill or in the oven until golden and bubbling.
Serve and enjoy.
