Chocolate yogurt

We love chocolate and especially my daughter. We love also natural yogurt. What better combination then? And what about adding to this a nutty flavor? Add some nuts in the yogurt and you'll give it a better taste.

Ingredients:

1l milk
125ml yogurt
100g black chocolate
1 tablespoon sugar
1 tablespoon vanilla extract
50g walnuts (cut in pieces)

Directions:

Boil the milk and let it cool until reaches 40ºC.
Melt the chocolate using a bain-marie. Add a bit of milk from the boiled one to make it more liquid.
Pour the chocolate into the remaining milk and mix until well combined.
Be sure that the milk chocolate do not exceed 40ºC and mix the yogurt in.
Add sugar and vanilla extract and mix all well.
Pour the composition in ceramic pots.
Add half teaspoon of cut walnuts in each yogurt pot.
Cover the pots with foil and tie them with rubber band.
Put the pots in the oven in a tray or on a baking stone at 50ºC for 1 hour and 30 minutes. Turn off the oven, without opening its door and let them stay inside over night. If you have a yogurt maker use it according to the instructions. I don't have one, and I really like to use my oven instead.
In the morning, put the pots in the fridge and serve them after 4 hours.