Preheat oven to 300 In medium bowl combine flour, soda and salt. Mix well with a wire whisk. Set aside. In large bowl with an electric mixer blend sugars at medium speed. Add butter and mix to form a grainy paste, scraping down side of bowl. Add eggs and vanilla, and beat at medium speed until light and fluffy. Add the flour mixture, pecans and white chocolate, and blend at low speed until just combined. Do not overmix. Drop by rounded tablespoons onto ungreased cookie sheets 2 inches apart. Bake 20-22 minutes or until edges just begin to turn golden brown. Use a spatula to transfer cookies immediately to a cool flat surface.