The word sounds like French, but I think it came to Indonesia through Dutch households during their colonial decades in many parts of Indonesia.
There are many versions of croquettes I've encountered and our favourite croquette is the one which is stuffed with either smoked chicken and cheese or cheese alone. I like to chop parsley to be blended together with potato mash but sometimes I just make them plain.
When using smoked chicken, I sometimes chop them finely and then mix them with herbed mashed potatoes. Other times, I just cut them into strips and stuff them inside the rolled potato mash together with cubed Edam, Mozarella, or Cheddar. This is the basic croquettes recipe I use though I usually only throw things in the bowl and don't rely on measurements. Simply modify to suit your personal taste.
300g potatoes, wash, steamed, peeled,
2 Tbs butter,
a good sprinkle of salt,
a good crack of blackpepper,
1 tsp milk,
50g cheese, diced thickly,
2 egg whites,
1-2 cups breadcrumbs or golden breadcrumbs,
oil for deep frying
Peel the skin off steamed potatoes. Mash the potatoes until smooth, add in butter, salt, pepper, and milk. Mix well. Whisk the egg whites loosely. Put the breadcrumbs in a plastic bag. Take a spoonful of potato mixture, roll into a ball, flatten, make slightly hollow in the middle, then put the smoked chicken (if using) and/or cheese. Fold the edges of the flatten dough, roll into a croquette shape. Dip into the egg whites, put into the breadcrumbs in the plastic bag, shake it until all covered with breadcrumbs. Keep the croquettes in the fridge for at least 30 minutes. Heat the oil. Fry the croquettes until golden brown. Serve warm.