Preheat your oven to 350°F (175°C). In a mixing bowl, toss the pecans with melted brown butter and a pinch of salt until evenly coated. Spread the pecans on a baking sheet in a single layer. Bake for 10 minutes, or until golden and fragrant, stirring halfway through. Chop the pecans and set aside to cool.

In a medium bowl, whisk together the cake flour, baking powder, and kosher salt. In a separate large bowl, combine the cooled brown butter, granulated sugar, light brown sugar, eggs, vanilla extract, and almond extract. Mix until smooth and creamy. Gradually add dry ingredients, alternating with milk until well combined. Gently fold in the chopped buttered pecans.

Line a muffin tin with cupcake liners. Fill each liner halfway with the cupcake batter. Bake for 18 to 22 minutes, or until a toothpick comes out clean. Allow cooling in the pan for 5 minutes before transferring to a wire rack.

In a mixing bowl, beat the cooled brown butter and powdered sugar together until smooth and creamy, about 2-3 minutes. Add vanilla extract, kosher salt, and enough milk or cream to achieve fluffy consistency. Beat for another 4-5 minutes until light and airy.

Once the cupcakes are completely cool, generously frost each with the buttercream using a spatula or piping bag. Sprinkle remaining buttered pecans on top for added crunch.