Preheat oven to 350º F (or 325º F for dark or nonstick pan). Place paper baking cup in each of 24 regular size muffin cups
In heavy 8 inch nonstick skillet, cook pecans and 2 tablespoons of the sugar over low heat about 8 minutes, stirring constantly, until sugar is melted. Spoon and spread pecans onto sheet of waxed paper. Sprinkle with remaining 1 tablespoon sugar; toss.
In large bowl, beat cake mix, pumpkin, water, oil, eggs and pumpkin pie spice with electric mixer on low speed 30 seconds. Beat on medium speed 2 minutes, scraping bowl occasionally. Divide batter evenly among muffin cups (about 2/3 full).
Bake 20 – 25 minutes or until toothpick inserted in center comes out clean. Remove from pan to cooling rack. Cool completely, about 30 minutes.
Frost cupcakes with frosting. Sprinkle edge of frosted cupcakes with pecans; press lightly into frosting.