Step by step

Method

5 steps

1. 1

   Heat the oven to 350°F. Line an 8-inch square pan with parchment, leaving overhang for easy lift-out.

2. 2

   Whisk ½ cup melted unsalted butter with 1 cup packed light brown sugar until thick and shiny. Beat in 1 large egg and 1½ teaspoons vanilla.

3. 3

   Stir in 1 cup flour, ½ teaspoon baking powder, and ¼ teaspoon salt just until combined. Fold in ¾ cup butterscotch chips and optional ½ cup chopped pecans.

4. 4

   Spread the thick batter evenly in the pan. Optional: a pinch of flaky salt on top. Bake 22–26 minutes until the top is golden, the edges look set, and a toothpick shows moist crumbs — the center should still look a touch soft; it firms as it cools.

5. 5

   Cool in the pan before lifting out and cutting into 16 squares. You want chewy butterscotch blondies with gooey centers — not cakey dry squares or a raw wet middle.