Whisk together first 3 ingredients in a large heavy saucepan; whisk in milk and next 2 ingredients. Bring mixture to a boil over medium heat, whisking constantly. Boil 1 minute, whisking constantly. Remove from heat.
Step 2
Whisk in butter and vanilla bean paste. Spoon pudding into serving dishes; cover and chill 4 hours. Dollop with sweetened whipped cream.