Divide the berries evenly between 4 - 6 shallow dessert bowls.
In a medium bowl, whisk together yolks and sugar.
In a 1.5-qt. sauce pan, bring the milk, cream and vanilla extract to a simmer. Remove the milk from the heat and slowly whisk in the egg mixture. Return the sauce pan to the heat, add thyme sprig and cook on low heat, stirring constantly with a wooden spoon.
When the mixture coats the back of the wooden spoon, remove from the heat and strain. Cool in an ice bath. Drizzle over the berries.
Refrigerate for up to 3 days.