Add
milk, egg yolks, and vanilla extract to a saucepan and whisk until thoroughly
combined.
In
a separate bowl, combine brown sugar, cornstarch and salt. Whisk into milk
mixture. Heat over medium-high heat until mixtures comes to a gentle boil,
stirring frequently. Reduce heat to medium and continue cooking until thick and
creamy. Remove from heat and whisk in butter.
Place
saucepan in a large bowl filled with ice and whisk pudding periodically until
chilled.
Divide
between 4 serving dishes, top with toasted pecans, and serve.