Leavened croissants

Directions

1. 1
   Mix together flour and butter until they combine.
2. 2
   Add sugar, egg yolk and mixture of yeast and milk.
3. 3
   Mix into smoothly dough.
4. 4
   Roll out the dough and cut up into squares.
5. 5
   Add optional filling.
6. 6
   Roll the squares in croissants.
7. 7
   Put the croissants on baking paper on baking tray and let them rise for 30min.
8. 8
   Coat them with mixed egg and bake them on 180C for 20 min or until they become golden brown.