In a blender, add labneh (or yogurt), cheese slices, eggs and sugar. Blend until smooth.
Remove the thin crust from the top of the bun and press in the middle to make it hollow.
Pour the blended mixture in the buns and bake in the air fryer or oven at 180°C for 8-10 minutes or until the buns are crisp and the custard topping is caramelized.