Dip with a metal ice-cream scoop into the hot oil, then scoop some of the batter with the ice-cream scoop and gently let the batter ‘drop’ in the hot oil. The batter will form immediately and float upwards. Depending on the size of your pan, you can fry several oliebollen at the same time. Just be careful not to overfill the pan. The oliebollen will expand a bit when they’re in the oil and they need space to cook properly.