My favorite brownie recipe is from Martha Stewart's Baking Handbook, so I started there. This is a very fudgy brownie recipe, comes together quite easily, and only uses one bowl! I spread half of the batter into a square baking pan and added a generous layer of chopped california brittles. I spread the second half of the batter over the top, and placed the whole thing in the oven.
I loved the end result - the california brittles partially melted into the dough, so these don't have a strong toffee flavor. Instead, every bite is a little bit different - sometimes you get a chunk of almond, other times you get a piece of milk chocolate. These brownies have a crackly top, which adds great texture but can be difficult to cut neatly. I chill the brownies thoroughly before cutting, which takes care of the problem.
1/2 cup unsalted butter, plus more for the pan
8 ounces semisweet chocolate, coarsely chopped
1 and 1/2 cups sugar
1 and 1/2 teaspoon vanilla extract
3/4 cup all purpose flour
1/2 teaspoon salt
1 cup almond toffee such as See's california brittles, coarsely chopped
Preheat the oven to 350 degrees F. Butter an 8 inch square baking pan. Line the pan with parchment paper, leaving an overhang on two sides. Set aside. Melt the butter and chocolate together in a bowl set over a pot of simmering water. Remove the bowl from the heat and set aside. Let the chocolate cool for about 7-10 minutes.
Stir the sugar into the cooled chocolate until combined. Add the eggs one at a time, whisking until smooth after each addition. Add the vanilla, and fold in the flour and salt.
Pour half the batter into the pan, spread in an even layer. Sprinkle the toffee over the batter. Add the second half of the batter to the pan, spread in an even layer over the toffee.
Place in oven and bake until a skewer inserted into the center comes out with only a few crumbs attached, 45-50 minutes. Transfer pan to a wire rack - after 10 minutes, run a knife around the edges of the pan, then cool completely, transfer to refrigerator and chill for at least 2 hours.