Pastry cream is the base of many French desserts such as fruit tarts, profiteroles, eclairs, mille feuilles cake etc. Most traditional recipes call for flour as a thickening agent, but using could lead to two difficulties. First, there is a chance that the flavor in your cream ends up undercooked which adds a rather unpleasant taste, and second it is a bit more difficult to control the thickness of the your custard when using flour (it may turn out runny). Using corn starch however, prevents both these problems.
6 eggs yolks at room temperature
3/4 cup granulated sugar
3 Tbs cornstarch
1 1/2 cup scalded whole milk
1 tsp vanilla extract
1 tsp of Cognac or French brandy
Place the yolks and the sugar in a medium sized bowl and beat with a mixer for about 3-4 minutes or until the mixture gets tick and pale.
With the mixer on low speed add the cornstarch, beat for 30 seconds.
With the mixer still on low slowly add the scolded milk. The milk should be hot but not boiling. Mix until just combined, about 10 seconds.
Transfer the mixture to a clean nonstick pan and cook over medium heat while constantly whisking for 5 minutes. The cream will become very tick.
Add the vanilla extract and the Cognac, give it a quick stir and pour the pastry cream into a medium glass bowl or jar. Place a piece of cling film directly on the surface of the cream to prevent the upper layer from drying.
Let it cool completely.