1 tablespoon plus 1 cup butter, softened, divided
1 1/2 cups coarsely chopped pecans, toasted
1 cup (6 ounce) semisweet chocolate chips
2 cups packed brown sugar
1 cup light corn syrup
1/4 cup water
1 (14 ounce) can sweetened condensed milk
2 teaspoons vanilla extract
Line a 13 x 9-inch baking pan with foil; butter the foil with the 1 tablespoon butter. Sprinkle with pecans and chocolate chips; set aside.
In a heavy saucepan over medium heat, melt remaining butter. Add brown sugar, corn syrup and water. Cook and stir until mixture comes to a boil. Stir in milk. Cook, stirring constantly, until a candy thermometer reads 248 degrees F (firm ball state).
Pour into prepared pan (do not scrape saucepan). Cool completely before cutting.
Yields about 2 1/2 pounds (about 6 3/4 dozen).