Preheat oven to 350°F (175°C).
Line cupcake pan with paper liners.
Toast pecans in dry skillet for 5 minutes.
Brown butter in saucepan until golden.
Cool butter for 10 minutes completely.
Mix flour, baking powder, and salt together.
Beat eggs and granulated sugar until fluffy.
Add cooled butter to egg mixture slowly.
Alternate buttermilk and flour mixture additions.
Fold in toasted pecans and vanilla extract.
Fill cupcake liners two-thirds full with batter.
Bake for 18-20 minutes until golden brown.
Cool in pan for 5 minutes first.
Transfer to wire rack for complete cooling.