Using an electric mixer, cream together butter and sugar at medium-high speed until light and fluffy, about 4 minutes. Add vanilla, flour, pecans and salt. Blend well. Gather dough into a ball, press into a flat disc, wrap and refrigerate for several hours or overnight.
Preheat the oven to 375°F. Scoop and roll dough into small teaspoon-sized balls and place on a non-stick baking sheet about an inch apart. Bake until just golden brown, 8 to 10 minutes. Remove, let sit for 1 minute then gently dredge cookies in sifted powdered sugar. Cool completely and recoat with powdered sugar.
Per Serving: Serving size: 2 cookies, 150 calories (100 from fat), 11g total fat, 5g saturated fat, 20mg cholesterol, 100mg sodium, 12g carbohydrates, (1 g dietary fiber, 4g sugar), 2g protein.