Here's the "1/2 failure" I mentioned earlier. These mini brownie bites tasted great, nice and chocolatey with a slightly crisp outside but fudgy goodness inside. The failure part was their appearance. The batter firmed up/cooled off faster than I expected and didn't really smooth out during baking so if they go into the mini muffin pan craggy, they come out craggy. They also didn't come out easily although I used a nonstick pan and had sprayed it with nonstick cooking spray to boot. I ran a little spatula around the sides to get them to release more easily but the firm outside meant the spatula met with resistance so sometimes the outside broke and the mini bites came out misshapen. It didn't affect their taste but this isn't something I'd parade in a magazine either. To salvage their appearance, I put them in festive little mini cupcake liners. That probably didn't fool anyone but it hid some of their Quasimodo-ness at first glance.
I kept the worst-looking ones as my taste test by putting a couple of them in a ramekin, warming them up in the microwave for 10-15 seconds and topping with vanilla ice cream. All was forgiven then.
1 cup (4 ½ ounces) coarsely chopped walnuts (I substituted mini chocolate chips instead)
3 ounces bittersweet chocolate (70 to 72% cacao content), finely chopped
3 ounces unsweetened chocolate, finely chopped
4 ounces (8 tablespoons, 1 stick) unsalted butter, cut into small pieces
2 extra-large eggs, at room temperature
2/3 cup (4 ounces) granulated sugar
2/3 cup (4 ounces) firmly packed light brown sugar
1 teaspoon pure vanilla extract
½ cup (2 ¼ ounces) all-purpose flour
2 tablespoons (½ ounce) unsweetened cocoa powder (natural Dutch-processed)
¼ teaspoon kosher or fine-grained sea salt
1. Position a rack in the center of the oven and preheat to 350˚F. Place the mini muffin pans on a baking sheet.
2. Toast the walnuts if using and cool completely.
3. Place the bittersweet chocolate, unsweetened chocolate and butter in the top of a double boiler over low heat. Stir often with a rubber spatula to help the chocolates and butter melt evenly. When melted, let cool, stirring occasionally to prevent a skin from forming.
4. Whip the eggs in the bowl of an electric mixer with the wire whip attachment until they are frothy. Add the granulated sugar and brown sugar and whip until the mixture is very thick and pale colored and holds a slowly dissolving ribbon as the beater is lifted, about 5 minutes. Mix in the vanilla. Add the melted chocolate and butter mixture and blend completely on low speed. Stop and scrape down the sides and bottom of the bowl with the rubber spatula.
5. In a medium-size bowl, sift together the flour and cocoa powder. Add the salt and stir to combine. In 3 stages, add this flour mixture to the chocolate mixture, blending well after each addition. Stop and scrape down the sides and bottom of the bowl with the rubber spatula. Add the walnuts, if using, (or chocolate chips) and stir to distribute evenly.
6. Use a1 ½” round ice cream scoop to divide the batter evenly among the cavities of the mini muffin pans, filling each cavity.
7. Bake the brownies for 25 minutes, until a cake tester or toothpick inserted in the center comes out slightly moist. Remove the baking sheet from the oven and transfer the mini muffin pans to racks to cool. Remove brownies from the mini muffin pans when they’ve cooled slightly.