Drizzle some olive oil on a pan and cook the onion on medium heat until it browns. Once the onion is done, add the cooked chicken and give it a quick mix. Add a pinch of salt and pepper.
Place the mixture into the food processor and chop it to a fine consistency. If you don’t have a food processor, use a blender or another substitute. Set it aside.
In a large pan, add 2 tablespoons of butter and cook in low heat until the butter melts. Once it’s melted, add 2 tablespoons of all purpose flour. Whisk constantly until the flour is brown. Add 1 1/4 cups of milk and the nutmeg and whisk until everything has been incorporated (it should like like a white sauce). *If it looks very thick, add the remaining 1/4 cup of milk. If its too liquidy, add another tablespoon of flour. You don’t want a liquid dough because it will be impossible to form the croquettes.
Place the chicken mixture into the pan and stir it. Keep stirring, you want all the ingredients to be fully incorporated.
Transfer the mixture onto a plate, let it cool down for about 20 to 30 minutes. Cover with a plastic wrap and transfer into the refrigerator.
The mixture should rest for a minimum of 2 hours, or overnight.
After the dough has rested, prepare the egg mixture. For this, I beat one egg and I put the bread crumbs onto a large plate.
Shape the mixture into small croquettes with a small spoon.
Once it’s ready, fry them! It is super fast. It takes me about 3 minutes total for each batch of croquettes.
Remove the croquettes and let them rest on a paper towel to cool and remove excess oil. Serve warm and… BON PROFIT!
Make Ahead: Prepare the recipe at night so the dough can rest overnight and you can fry them the next day.