Black Widow Bars
1/4 cup unsalted butter, melted and hot
1/4 cup peanut butter, preferably chunky variety
1 cup dark brown sugar, packed
3 large eggs
2 teaspoons vanilla extract
1 1/3 cups all-purpose flour
1/2 teaspoon baking powder
1 cup semi-sweet chocolate chips, coarsely chopped
1/2 cup unsalted butter, melted and hot
1 cup semi-sweet chocolate chips
2 2/3 cups powdered sugar, divided
3/4 cup dark chocolate syrup
1/4 cup plus 1 tablespoon milk
Heat oven to 350 degrees. Very lightly grease bottom of 9-inch round baking pan. Line bottom with parchment or wax paper.
For the bars: In a heatproof mixing bowl, whisk together melted butter and peanut butter until smooth. Add brown sugar, eggs and vanilla, whisking until smooth. Add flour and baking powder. Stir with spoon until moistened. Stir in 1 chopped chocolate chips and scrape bowl well.
Spoon into prepared pan and bake for 25-30 minutes just until tester inserted in center comes out clean. Cool 15 minutes in pan. Run knife around pan edge to loosen. Turn onto cake plate and remove paper. Cool 30 minutes before frosting.
For the frosting: In a 4-cup Pyrex measure or heatproof bowl, combine hot melted butter with semi-sweet chips. Stir continuously until chocolate melts and mixture is smooth. Add 1 cup powdered sugar and 1/4 cup of the chocolate syrup. Stir until combined. Mixture will thicken and become stiff. Add remaining 1 cup powdered sugar, 1/4 cup milk and 1/4 cup chocolate syrup. Stir until smooth. Allow frosting to stand 2 minutes. Add remaining 1/4 cup chocolate syrup, adjusting if too stiff. Frosting should appear smooth and satiny. Frost top and sides of cake. Set aside.
For the web decoration: In a small bowl, combine 2/3 cup powdered sugar and 1 tablespoon milk. Stir until smooth, adding milk until a slightly runny glaze forms. Spoon into a small decorating bag fitted with a round writing tip. Alternatively, pour glaze into a small plastic bag and snip off the corner to create a tip.
Work quickly; do not allow fudge frosting to dry. Starting in the center of cake, using white glaze, pipe circles on top about 1/2 inch apart. Using cake tester or toothpick, lightly drag lines through the frosting, from outer edges of cake to center, about 1 inch apart. Decorate with spiders and cut into small wedges. Store at room temperature.
Baker's hint: For an enhanced chunky texture, add 1/2 cup chopped nuts to the bar base before baking.