12tablespoons(170g)salted butter, 1 1/2 sticks, melted and cooled slightly
1cup(212g) light brown sugar
½(106g)cup granulated sugar
1large egg yolk
2cups + 2 tablespoons(298g)all purpose flour
2cups(340g)chocolate chips or chocolate chunks, semisweet, bittersweet, milk, white, peanut butter…the options are endless!
Preheat the oven to 325 degrees. Adjust the oven rack to lower-middle position. Line a 9X13-inch baking pan with foil, letting the excess hang over the edges of the pan by about 1 inch so you can grab those edges and pull the brownies from the pan after they have baked. Spray the foil-lined pan with nonstick cooking spray.
In a large bowl, whisk together the melted butter, salt and baking soda together until well combined. Add the brown sugar and granulated sugar and stir until evenly combined. Add the egg, egg yolk, and vanilla and mix well.
Add the flour. Using a rubber spatula or wooden spoon start folding the flour into the wet ingredients. After a few stirs (with streaks of flour remaining), add the chocolate chips or chocolate chunks and mix until combined. Don't overmix, just stir until no dry streaks remain (sometimes I use my hands as the dough gets thick).
Press the batter evenly into the prepared pan.
Bake until the bars are light golden brown on the edges, slightly firm to the touch, and edges start pulling away from sides of pan, 24-28 minutes. Cool on a wire rack to room temperature. Remove the bars from the pan by lifting the foil overhang and transfer them to a cutting board. Cut into squares and serve.
Original Recipe: the original recipe posted way back in 2010 used two bowls (whisking the dry ingredients in a separate bowl), but taking notes from this awesome recipe, I've changed up the mixing for this recipe so it can be a strictly one bowl recipe. If you are a die-hard fan of the original, just mix the flour, baking soda, and salt together in a small bowl and add it after the wet ingredients are mixed. Everything else in the recipe is the same as before.