It’s no wonder kids adore these bar cookies. A gooey topping spills over a base filled with butterscotch chips, miniature marshmallows, chocolate chunks, and—as if that weren’t enough—melted caramels.

　　

Ingredients

makes about 16

　　2 1/4 cups all-purpose flour

　　2 1/4 teaspoons baking powder

　　1 teaspoon coarse salt

　　1/2 cup (1 stick) unsalted butter, room temperature, plus more for pan

　　1 1/2 cups packed dark brown sugar

　　3 large eggs

　　1 teaspoon pure vanilla extract

　　1 cup miniature marshmallows

　　1 cup semisweet chocolate, coarsely chopped

　　1 cup white chocolate, coarsely chopped

　　1 cup butterscotch chips

　　18 soft caramel-candy cubes, coarsely chopped

　　

Step 1

Preheat oven to 350°F. Lightly butter a 9 by 13-inch baking pan. Line with parchment, allowing a 2-inch overhang on the longer sides. Brush parchment with butter (not overhang).

　　

Step 2

Whisk together flour, baking powder, and salt in a bowl. Using a wooden spoon, mix butter and brown sugar in a medium bowl until fluffy, about 2 minutes. Add eggs and vanilla; mix until well combined. Mix in flour mixture until combined. Fold in half of each of the marshmallows, chocolates, butterscotch chips, and caramels.

　　

Step 3

Spread batter in prepared pan. Scatter remaining marshmallows, chocolates, butterscotch chips, and caramels on top. Bake until top is golden brown and a cake tester inserted into center comes out clean, about 35 minutes. Let cool on a wire rack. Lift out of pan, and transfer to a baking sheet. Refrigerate until set, at least 30 minutes.

　　

Step 4

Remove parchment, and cut into about 16 triangles. Bars can be stored in an airtight container at room temperature up to 1 week.

　　Martha Stewart's Cookies