Step 1

Add the milk and 1/4 cup of sugar to a medium sauce pot, and whisk to combine.

Step 2

Bring to a boil over medium heat, stirring often.

Step 3

While heating, in a large bowl, add the egg yolks, whole egg, cornstarch, and remaining 1/3 cup granulated sugar. Whisk until smooth.

Step 4

Once the milk comes to a boil, very slowly drizzle the hot milk into the egg mixture while whisking constantly.

Step 5

Add all of the milk to the egg mixture, then transfer everything back into the sauce pot.

Step 6

Over medium heat, bring it back up to a boil, stirring constantly.

Step 7

Once the mixture reaches a boil, remove from the heat and stir in the butter until melted.

Step 8

Then, stir in the vanilla.

Step 9

Pour into a medium bowl and immediately cover with plastic wrap so the plastic touches the top of the pastry cream, so a skin does not form on top. Place in the fridge until cold.