Creme Patissière (Pastry cream)

Ingredients:
1 liter of milk
8 egg yolks
200 g sugar
140 g all purpose flour
1 vanilla bean or a tsp of vanilla essence

Method:
Boil 1 litre of milk in a thick-bottomed vessel with 1 vanilla bean split, preferably inox ( Avoid using Aluminium vessels for preparations in which eggs are used) & keep it hot.
In a bowl, whip the egg yolks with the sugar until the cream becomes beige in color.
Now, add the flour & mix once again.
Pour the boiling milk slowly, while whipping the mixture continuously. Remove the vanilla bean.
When everything has been well mixed, pour this in a thick bottomed vessel once again & cook on high flame for about 2 to 3 minutes, while whipping vigorously & by scraping the bottom of the vessel to prevent the attachment of the cream. Be careful not to burn the cream.
Leave it to cool down and pat the surface with some butter to prevent the crust on the top of the cream. I pour it in a wide vessel for faster cooling. This is the ?crème patissiere?.