Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. Toss the pecans with melted brown butter and a pinch of salt, then bake for about 10 minutes.

In a bowl, whisk together the cake flour, baking powder, and kosher salt. In another bowl, mix the cooled brown butter with sugars, eggs, and extracts. Gradually add the flour mixture and whole milk, then fold in pecans.

Spoon the batter into lined cupcake liners, filling halfway. Bake for 18 to 22 minutes, then cool in the pan for 5 minutes before transferring to a wire rack.

For the frosting, cream together the brown butter and powdered sugar until smooth. Mix in vanilla, salt, and milk until fluffy.

Frost cooled cupcakes and sprinkle with remaining buttered pecans before serving.