Add in the dissolved gelatin and stir until well combined.
Remove from the heat and spread out the sauce in a baking dish or plate.
Cool for about 30-60 minutes then cover and refrigerate for at least 2 hours or overnight.
Breading
After refrigeration, the mixture would have hardened. With a spoon, scoop out enough cheese mixture to form into a ¾ - 1-inch ball (2½ cm).
Roll the ball in the plain flour; then dip in the beaten egg; then roll in the breadcrumbs. (The breading may be repeated if you want a thicker crust.) Do the same for the rest of the mixture.
1 cup all-purpose flour, 2 eggs, 1 cup breadcrumbs
Place the balls on a plate and repeat for the rest of the filling. Cover and refrigerate for 30 minutes.
At this point you may freeze the bitterballen if you wish.
Deep frying
Heat your frying pan to 350°F/180°C (medium heat). Check the temperature by placing a small cube of bread in the heated oil. It should sizzle and brown in a minute or two.
sunflower oil
Deep-fry the bitterballen for 3-4 minutes until golden. (For frozen bitterballen, add 1 more minute in the frying time.)