Super Soft Croissants

400 ml 1 3/4 cups warm milk

100 g 1/2 cup sugar

7 g dry yeast

1 egg

15 ml 1 tbsp oil

pinch of salt

10 g 2 tsp vanilla sugar

600 g 3 3/4 cups flour (6 glasses of 200ml)

100 g 7 tbsp butter, melted