A few tips:There’s a light crunchy

A few tips:

There’s a light crunchy crust on top, that some reviewers complained about online. I’m not sure why the crust forms, but it didn’t bother me at all. Just make sure to give these brownies time to cool before you need to cut into them. They’re so moist and delicate that they need that time to firm up. The crust settles down a bit, too. Cut them with a very sharp knife and they’ll look perfect.
Use a good chocolate. I ran to the store and grabbed some Ghirardelli bittersweet chocolate bars (they’re worth every penny, even at $3.68 a bar).
Chocolate Mocha Brownies
Adapted from Bon Appétit, September 1999

Nonstick vegetable oil spray
8 ounces bittersweet (not unsweetened) or semisweet chocolate, chopped
3/4 cup (1 1/2 sticks) unsalted butter
2 cups sugar
6 large eggs (The secret to the moistness!!)
2 teaspoons vanilla extract
1/2 cup all-purpose flour
1/3 cup unsweetened cocoa powder (I used Ghiradelli – you can’t go wrong with it.)
1 teaspoon instant espresso powder (This didn’t sound like enough, so I added a little more – maybe 1 1/2 teaspoons. . . But I wouldn’t add any more than that.)
1/2 teaspoon salt
1/4 cup sour cream
3/4 cup chopped walnuts
Powdered sugar (I used whipped cream instead, but the original recipe recommends dusting these with powdered sugar)

Preheat oven to 375 degrees. Then spray a 13×9x2-inch metal baking pan with nonstick spray (I don’t own a 13×9 inch pan, so I used two cake pans instead). Line the pan with parchment paper, letting the ends hang over two sides so you can use them as handles to pull the brownies out. (I didn’t have any parchment or waxed paper, so I used foil. Worked fine. . .) Now, hit the paper with a little nonstick spray.

Stir chocolate and butter in heavy small saucepan over low heat until melted. (Don’t overheat the chocolate! I used the double-boiler method just to be safe – boiling water in a pot and then putting the chocolate and butter in a bowl over it.) Cool to lukewarm.

Using electric mixer, beat 2 cups sugar, eggs and vanilla in medium bowl until fluffy – give it about 5 minutes. Add the chocolate mixture and beat just until blended. Then add the flour and next 3 ingredients, beating until just blended. Stir in sour cream and nuts.

Pour the batter into your prepared pan. Bake until tester inserted into center comes out with moist crumbs attached, about 35 minutes. Cool completely on a cooling rack. Then carefully remove from the pan, using your handles. With a sharp knife, cut the brownies into squares. Serve with whipped cream or a simple dusting of powdered sugar.