Step 1

In a medium saucepan, combine sugar, cornstarch, and salt. In a medium bowl, whisk milk and egg yolks; gradually stir into saucepan.

Step 2

Cook over medium heat 8 to 10 minutes, or until mixture thickens and is bubbling, whisking constantly.

Step 3

Remove from heat and stir in butter and vanilla. Spoon into individual serving dishes or a large bowl.

Step 4

Cover with plastic wrap directly on surface of pudding and refrigerate 4 hours, or until firm.