These cookies were pretty labor intensive, between all the chopping of chocolate and Heath bars and the double boiler step. It was absolutely worth it, though; the cookies were rich and chocolatey and the toffee pieces were scrumptious.
Melly hung out with me in the kitchen while I baked. I tried to take some pictures of her being her usual adorable self, but I just got a lot of this:
Here's the recipe:
Adapted slightly from Smitten Kitchen
1/2 cup all purpose flour
1 teaspoon baking powder
1/2 teaspoon salt
1 pound semisweet chocolate, chopped
1/4 cup (1/2 stick) unsalted butter
1 1/2 cups (packed) brown sugar
4 large eggs
1 tablespoon vanilla extract
5 1.4-ounce chocolate-covered English toffee bars (such as Heath), coarsely chopped
1 cup walnuts, toasted, chopped
Combine flour, baking powder and salt in small bowl; whisk to blend. Stir chocolate and butter in top of double boiler set over simmering water until melted and smooth. Remove from over water. Cool mixture to lukewarm.
Using electric mixer, beat sugar and eggs in bowl until thick, about 5 minutes. Beat in chocolate mixture and vanilla.
Stir in flour mixture, then toffee and nuts. Chill batter until firm, about 45 minutes.
Preheat oven to 350°F. Line 2 large baking sheets with parchment or waxed paper. Drop batter by spoonfuls onto sheets, spacing two inches apart. Bake just until tops are dry and cracked but cookies are still soft to touch, about 12 to 15 minutes. Cool on sheets. (Can be made 2 days ahead. Store airtight at room temperature.)