Heat the oven to 350°F and line two 12-cup muffin pans with paper liners. Spread the pecans on a baking sheet and toast them for 5 to 8 minutes, until fragrant; cool before mixing them into the batter.

Whisk the butter pecan cake mix, instant vanilla pudding mix, eggs, vegetable oil, water, and Crown Royal whisky in a large bowl until smooth. Stop mixing as soon as the ingredients are combined so the cupcakes remain tender.

Fold 1 cup of the cooled, finely chopped toasted pecans into the batter. Divide the batter among the liners, filling each approximately two-thirds full.

Bake for 18 to 22 minutes, or until the tops spring back lightly and a toothpick inserted in the center comes out clean. Cool the cupcakes in the pans for about 5 minutes, then transfer them to a rack to cool completely.

For the frosting, beat the softened butter until creamy. Gradually add the sifted confectioners' sugar, then beat in the vanilla, Crown Royal, optional salt, and enough heavy cream or milk to create a smooth, pipeable consistency.

Pipe or spread the buttercream over the completely cooled cupcakes. Finish with the remaining toasted pecans and, if desired, a light caramel drizzle.