Prepare all ingredients:
Peel and chop a 2 cm long piece of ginger in a hollow bowl.
Add the juice of 2 lemons and mix well.
Cut the monkfish in 3 cm long pieces.
Marinate them with the lemon juice in the fridge for 1 hour turning them from time to time.
Cut the onions in quarters.
Drain the pieces of monkfish and stick them on bamboo skewers alternately with onion quarters.
In a small bowl, slighltly beat the egg whites using a fork.
Dip the skewers in the egg whites...
...then in the cornflour. Repeat by dipping the skewers in egg whites then cornflour once again.
Fry the skewers for 2 to 3 minutes...
...in hot oil.
Drain and serve immediately along with lemon quarters.