In a bowl, make 3 wells and add sugar, yeast and salt respectively. Gently mix

Add butter and combine until mixture is crumbly. Now add milk and mix until dough just comes together. Wrap the mixture in cling wrap and freeze for 30 minutes

On lightly floured surface, roll the dough in rectangular shape and cut in equal triangle. Place chopped chocolate towards wider edge. Roll the croissant from wide to tip and place them on greased baking tray with tip facing downwards. Cover the croissant with greased plastic wrap and allow to sit for 2 hours at room temperature

Preheat oven to 200. Brush croissants with egg wash. Bake for 8 minutes. Reduce temperature to 180 and bake for 12-16 minutes until deep golden brown. Cool on wire wrack and serve