2 tbs sugar
2 tbs potatoe starch flour (could use corn starch)
2 tbs unsweetened cocoa powder
1 1/2 cups milk
1/2 cup heavy cream
4 oz milk chocolate (3/4 cup)
1 tsp vanilla (I used Madagascar Bourbon last time, could use Mexican)
Whisk together sugar, starch, cocoa powder and a pinch of salt in a 2 quart pan, then gradually whisk in milk and cream. Bring to boil over moderately high heat, whisking constantly, then boil whisking 2 minutes. It should be thick at this point. Remove from heat and add chocolate and vanilla. Transfer to bowl, cover surface with waxed paper to prevent skin, chill at least 2 hrs.