Let the détrempe dough rest for 14/16 hours at 4°C.
Enclose the butter and let rest 10 minutes in the fridge at 4°C.
Make a 3-fold and then store 30 minutes in the fridge.
Make a 4-fold and then store 30 minutes in the fridge.
Laminate, cut and form the croissant.
Let rise 3 hours at 25°C with 60% humidity.
Brush with egg.
Bake at 170° for 25 minutes.
