Preheat the oven to 350°F (175°C). Place 2 tablespoons of butter on a baking sheet and let it melt in the oven.

Once melted, add 1½ cups pecans to the sheet, tossing them to coat evenly with the butter. Spread the pecans out in an even layer.

Toast the pecans for 5 to 7 minutes, stirring halfway through to ensure even roasting. Keep an eye on them as they can brown quickly. Once golden and fragrant, remove from the oven, allow to cool, then chop.

Reserve 1¼ cups of the chopped pecans for the cake batter. Set aside the remaining ¼ cup to sprinkle on top of the cupcakes later (adjust as desired).

Preheat the oven to 350°F (175°C) and line a cupcake pan with paper liners.

In a large mixing bowl, sift the cake mix, then add in the instant vanilla pudding mix, flour, dark brown sugar, eggs, sour cream, water, oil, and vanilla extract.

Mix on low speed for 10-15 seconds to incorporate the ingredients, then increase to medium speed and beat for 2 minutes. Pause occasionally to scrape down the sides of the bowl for even mixing.

Carefully fold in the 1¼ cups of chopped, buttered pecans until evenly distributed throughout the batter.

Spoon approximately ¼ cup of batter into each cupcake liner, filling them evenly.

Bake the cupcakes for 15-17 minutes, or until the tops spring back when lightly pressed, and a toothpick inserted into the center comes out clean or with only a few crumbs.

Remove the cupcakes from the pan shortly after baking and place them on a wire rack to cool completely.

Place the softened butter in the mixing bowl and beat on low to medium speed until smooth and creamy.

Add the softened cream cheese, cut into pieces, and continue beating on low to medium speed until thoroughly combined. If using a hand mixer, ensure the cream cheese is very soft for easier blending.

Add the vanilla extract and gradually sift in the powdered sugar, mixing on low speed to prevent a sugar cloud. Cover the bowl with a towel if needed to contain the powdered sugar.

Increase the speed and beat the frosting until light and fluffy. Avoid over-mixing to keep it from becoming too soft. If the frosting becomes too soft, refrigerate it briefly to firm it up.

For the best piping results, use the frosting while it’s still slightly chilled. You can prepare it in advance and refrigerate; before using, let it soften at room temperature (do not microwave), then remix gently.

Ensure the cupcakes are completely cooled before applying the frosting. Using a piping bag fitted with a large star tip, such as a 1M or 2D, pipe swirls of frosting onto each cupcake.

Finish by sprinkling the reserved buttered pecans on top for a decorative and flavorful touch.