Religious (cheese)

Religieuse (cheese): In Switzerland and in some regions where cheese fondue is eaten, we call “religious”, the rest of the cheese (crispy, but not burnt) which is attached to the bottom and in the center of the caquelon (See Caquelon), where the stove fire burns.
Some amateurs break an egg yolk to make it softer and thus bind the cheese.
The question remains open on the name of this crust which remains at the bottom of the pot when the fondue is finished ...