These bar cookies feature two layers of decadence — chocolate chip cookie and brownie. Additional butter and egg in this cookie dough give the bars a chewier texture.

　　

Ingredients

Makes 48 (2- by 1-inch) bars

　　Brownie batter , left in bowl

　　

For chocolate chip cookie dough

1 1/2 cups all-purpose flour

　　3/4 teaspoon baking soda

　　3/4 teaspoon salt

　　1 1/2 sticks (3/4 cup) unsalted butter, melted and cooled slightly

　　3/4 cup packed light brown sugar

　　1/2 cup granulated sugar

　　2 large eggs

　　3/4 teaspoon vanilla

　　1 1/4 cups semisweet chocolate chips (8 ounces)

　　

Step 1

Put oven rack in middle position and preheat oven to 350°F. Grease a 13- by 9- by 2-inch baking pan and line bottom and sides with wax paper, then butter paper.

　　

Step 2

Spread brownie batter evenly in pan.

　　

Make chocolate chip dough:

Step 3

Whisk together flour, baking soda, and salt in a small bowl.

　　

Step 4

Beat together butter and sugars in a large bowl with an electric mixer at high speed until pale and fluffy, 2 to 3 minutes. Lightly beat 1 egg with a fork in a small bowl and add 1 3/4 tablespoons of it plus remaining whole egg to butter mixture, beating with mixer until creamy. Beat in vanilla. Reduce speed to low and mix in flour mixture until just blended, then stir in chips.

　　

Step 5

Top brownie batter evenly with spoonfuls of cookie dough, spreading gently with back of spoon to form an even layer.

　　

Step 6

Bake until a wooden pick or skewer inserted in center comes out with moist crumbs adhering, about 1 1/4 hours. Cool completely in pan on a rack, about 2 hours. Invert onto a cutting board, remove paper, and cut into bars.

　　Cooks' note:

　　Cooled dream bars keep, layered between sheets of wax paper, in an airtight container at room temperature 2 days.