I'm terribly confused and frustrated with my pastry cream, and can't understand why, after years of beautiful results, I now consistently get tiny starch granules and often also pastry cream lumps that do not smooth out even with a little 'paddling'.
My current formula:
Milk - 2K
Sugar - 100
Vanilla - 15
Cornstarch - 200
Butter - 100
I originally began making this 2X (beginning with 4K soymilk, as I was working in a Kosher patisserie) and always had
wonderful results. Later, as I ventured to other kitchens, I began using whole milk. Again, great results.
Later, as I started my own business and began making smaller batches (often 1/4X or 1/8X) in my home kitchen, I still never had trouble. Now, working out of a commercial catering kitchen- this lump and granule business just about EVERY time.
I always use flat-bottomed pots with straight sides, bring the milk to a boil, sift sugar & cornstarch and whisk yolks super-smooth after adding it. I constantly whisk after adding tempered yolks/sugar/cornstarch to boiling milk, bring the thickened mixture to a boil, add butter to finish, then spread in plastic-wrapped sheet pans to cool. I always cover surface with plastic film as well. Sometimes I pass it through a china cap, before spreading into pans but that's VERY labor-intensive, or I will burr mix if I have mine handy. Nothing seems to help.
I have tried cooking longer (even after the initial boil of cream) , cooking at a lower temp. so it takes longer to thicken, and fine sifting the sugar/cornstarch. It seems that I keep finding tiny (uncooked?) starch granules in the cream, and even when it appears smooth and beautiful right after cooking; there are lumps that won't smooth out. Too much paddling makes the cream too soft too pipe into profiteroles or use as a cake filling. I nearly always fold fresh whipped cream into my cooled pastry cream (about 30% of total cream wt.)
Any advice you can offer is appreciated. I have tried cooking in different pans on different heat sources- no help.
Thanks so much-