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Warm Chocolate-Chunk Blondie Bars

in quick and easy whole grain dairy free gluten free overnight guaranteed classic


Bar cookies, whether brownies, blondies, or filled, are the workhorses of the baker's kitchen. They generally require one bowl and one pan, are agreeable to all sorts of added ingredients, cut cleanly for serving, always sell out at bakesales, and are sturdy travelers in the mail. Served slightly warm, bar cookies can be topped with ice cream for a sigh-inducing snack or dessert.

At a glance

one 9" x 13 " pan, or one 10" x 15" pan, 24 to 35 servings


Choose your measure:

  • 2/3 cup (10 tablespoons + 2 teaspoons) unsalted butter, melted
  • 2 cups light or dark brown sugar, firmly packed
  • 1/4 cup granulated sugar
  • 1/2 teaspoon salt
  • 1 tablespoon vinegar, white or cider
  • 3 large eggs
  • 1 teaspoon espresso powder
  • 2 teaspoons Vanilla
  • 2 1/2 teaspoon baking powder
  • 2 3/4 cups King Arthur Unbleached All-Purpose Flour or King Arthur White Whole Wheat Flour
  • 2 cups chocolate chips
  • 2 cups (approximately) coarsely chopped nuts (pecans, walnuts, or almonds)


  1. Preheat the oven to 350°F. Lightly grease a 10" x 15" jelly roll pan or a 9" x 13" pan.
  2. Combine the butter, sugars, salt, and vinegar, stirring to combine. If the mixture is hot from the melted butter, let it cool to lukewarm.
  3. Add the eggs, espresso powder, vanilla, and baking powder, beating well.
  4. Stir in the flour, mixing thoroughly, then the chocolate chunks and nuts.
  5. Scoop the batter into the prepared pan, using your wet fingers to smooth the top.
  6. Bake the bars for 30 minutes (for the jelly roll pan), or about 38 minutes (for the 9" x 13" pan), until the top is golden and shiny, and the center is just barely baked through. Use the sharp tip of a knife to peek into the center; it should be very damp, but not unbaked.
  7. Remove the bars from the oven, and cool to lukewarm before cutting.
  8. Store, well-wrapped, for 5 days, or freeze for longer storage.