Open the vanilla pod, scrape down the seeds and stir them into the milk. Place the whole pod into the milk, set aside for 15 min.
Melt chocolate over hot water (or microwave), stirring constantly.
Heat the milk with vanilla pod until just boiled. Dispose the vanilla pod.
Mix sugar, flour and salt, and blend with chocolate, this doesn't mix very well but will come together once the milk is added. Stir in 1 cup of the hot milk and beat until smooth, then cook over direct heat until mixture boils, stirring constantly.
Stir rest of hot milk slowly into beaten egg yolks, add to chocolate mixture and cook 5 minutes longer over boiling water**, stirring constantly.
Remove from heat. Let cool and serve warm or refrigerated.
*scalded meaning it has been once brought nearly to a boil, this is done so the vanilla pod can release it's flavor into the warm milk. This step is not necessary if using vanilla extract.
**I continued cooking it in the pan on a very low heat, just because I felt it was unnecessary to cook it over simmering water. Remember to always stir.