Put 2 cups sugar, milk, and butter in heavy saucepan over medium heat. Cook to softball stage, 234 degrees F. When almost ready, caramelize the remaining 1 cup sugar in another heavy skillet, preferably cast iron, over medium heat, stirring often, so sugar does not get too dark. As soon as sugar granules are totally dissolved, turn off heat and carefully add a few spoonfuls of candy mixture to caramelized sugar liquid, stirring constantly and thoroughly. Pour all back into saucepan of candy and mix quickly with wire whip or cooking spoon. Remove from heat. Add vanilla and continue beating candy for 10 to 15 minutes or as long as it takes for candy to lose its sheen and begin to thicken. Quickly stir in pecans and, using 2 soupspoons, scoop small mounds onto papered cookie sheets. Let set. Store in covered tins.
If candy gets too hard before it is all scooped, place in safe container and warm in microwave until of good consistency to finish scooping.
Professional Recipe: This recipe was provided by a chef, restaurant or culinary professional and makes a large quantity. The Food Network Kitchens chefs have not tested this recipe in the proportions indicated and therefore cannot make any representation as to the results.