Add sugar, cornstarch, milk, heavy whipping cream, sour cream and salt to a double boiler and whisk until the mixture begins to thicken.

Gradually add egg yolks into the mixture and whisk for another few minutes until thick.

Then remove from heat.

Add butter and vanilla, and blend in.

Pour into an airtight container and let cool completely before usage.

Store the pudding cream in the fridge, if you don’t plan to use it the same day.