Step 1

Whisk sugar, cornstarch, and salt together in medium saucepan

Step 2

Add milk and egg yolks, whisk to combine

Step 3

Bring to boil over medium heat, whisking or stirring constantly (6-8 minutes)

Step 4

When thick (like pudding) remove from heat and stir in butter, vanilla and chocolate (if using)

Step 5

Pour into jar, bowl, or other container and lay plastic wrap across the surface, being sure it is touching the surface (to prevent a skin from forming)

Step 6

Place in refrigerator for several hours, or until chilled

Step 7

Once chilled you can remove the plastic wrap and just use the container's lid to cover