Knead all ingredients, except the Croissant Butter (2) for 8 minutes.
Place the dough in a small container and let rise for 1 hour at ambient temperature.
Allow to rest in the refrigerator for 1 night.
Stretch the dough in the dough sheeter, so the Croissant Butter sheet fits on the dough.
Fold the dough over the butter and close.
Give a single (1x3) and a double tour (1x4).
Store in the refrigerator overnight.
Laminate the dough to a thickness of 7mm and shape the croissants.
Place on trays to ferment 2 à 2,5 hours at 27°C.
Cut the croissant dough of 5 cm by 20 cm.
Fold and shape the strips in a cube baking tin.
Bake at 170°C during 20 minutes.