MARTHA'S PECAN BARS

Steps:

• Preheat oven to 375 degrees. Brush a 9-by-13-inch baking pan with melted butter. Line with parchment paper, leaving a slight overhang on all sides. Butter parchment; set aside.
• Make crust: Place butter and brown sugar into the bowl of an electric mixer fitted with the paddle attachment; mix on medium speed until light and fluffy, about 2 minutes. Mix in salt. Add flour, 1 cup at a time, mixing until fully incorporated after each addition. Continue mixing until dough begins to come together in large clumps.
• Press dough about 1/4-inch thick into prepared pan. Pierce the dough with a fork. Chill until firm, about 20 minutes. Bake until golden brown, 20 to 22 minutes. Transfer to a wire rack to cool completely. Reduce oven to 325 degrees.
• Make filling: Place ingredients in a saucepan over high heat. Bring to a boil, stirring constantly until mixture coats the back of a spoon, about 1 minute. Remove pan from heat; pour filling into the cooled crust.
• Bake until filling bubbles, 15 to 20 minutes. Carefully transfer to a wire rack to cool completely. Run a paring knife around edges of the pan and invert onto cooling rack. Invert again onto a cutting board. Use a sharp knife to cut into 1-by-3-inch bars. Bars can be stored in an airtight container at room temperature up to 1 week.