Step 1

In a medium saucepan over low-medium heat add the half and half and espresso powder. Let cook for a couple of minutes to warm it up - do not boil the cream.

Step 2

While half and half is warming, in a medium bowl whisk together the egg yolks, corn starch, salt, and sugar. Whisk for two minutes, the mixture should be much lighter in color.

Step 3

Once the liquid mixture is warmed slowly add a little bit to the egg mixture and whisk to combine. Then add all of the cream slowly and whisk to combine.  (If you do this all at once, fast, you will scramble the eggs)

Step 4

Add all of the mixture back to the pot and cook over low-medium heat for another couple of minutes, whisking constantly. The mixture will thicken up. You want it quite thick, the mixture will "burp" bubbles will pop on the surface- this shows it is done.

Step 5

Take the pot off the heat and immediately add the cold butter and vanilla bean paste whisking vigorously to combine. Then pour into an air-tight container, place plastic wrap on top and push directly on top this helps prevent a thick skin from forming. Let chill in the fridge for at least three hours or up to three days. Rewhisk the pastry cream before serving.