Thick Pastry Cream

excuse me while I ran to the sink for 30 seconds after cooking the cream.

2 c. 1/2 & 1/2,
2 c. milk,
1/2 c. + 3 T. sugar,
6 T. corn starch,
1 T. pure vanilla extract and 1 T. rum extract ( more if you like).
12 large egg yolks ( eggs weigh 2 oz. ea) ,
6 T cut up unsalted butter.

my cost-------$5.7