1. Preheat oven to 350°. Line bottom and sides of an 8-inch pan with aluminum foil, allowing 2 to 3 inches to extend over sides; lightly grease foil.
2. Microwave chocolate squares and butter in a large microwave-safe bowl at HIGH 1 1/2 to 2 minutes or until melted and smooth, stirring at 30-second intervals. Whisk in granulated and brown sugars. Add eggs, 1 at a time, whisking just until blended after each addition. Whisk in flour, vanilla, and salt.
3. Pour mixture into prepared pan.
4. Bake at 350° for 40 to 44 minutes or until a wooden pick inserted in center comes out with a few moist crumbs. Cool completely on a wire rack (about 1 hour). Lift brownies from pan, using foil sides as handles. Gently remove foil, and cut brownies into 16 squares.
Test Kitchen Secret: Fast Stir-ins
Prepare the brownie batter as directed through Step 2. Add a few ingredients, tweak the baking times, and get ready to experience brownies unlike any we've discovered.
Caramel-Macchiato Brownies: Coffee fiends: Go with 1 Tbsp. espresso powder. Be advised—these are sticky! Avoid them if you wear braces.
Stir 1 cup miniature marshmallows, 1/2 cup caramel bits*, and 1 1/2 tsp. to 1 Tbsp. instant espresso into batter. Increase bake time to 44 to 46 minutes.
*12 caramels, quartered, may be substituted.
Note: Be sure to insert wooden pick into brownie, not marshmallow, when testing for doneness. (Marshmallows will rise to the top when baking.) We tested with Kraft Caramel Bits.
White Chocolate-Blueberry Brownies: A taste of chocolate-covered blueberries gave our Food staff this idea.
Stir 1 (3.5-oz.) package dried blueberries and 1 (4-oz.) white chocolate bar, coarsely chopped into batter. Increase bake time to 44 to 46 minutes.
Note: We tested with Sunsweet Dried Blueberries and Ghirardelli White Chocolate Baking Bar.
Toasted Coconut-Cashew Brownies: This spicy, nutty brownie got our top rating.
Spread 1 cup sweetened flaked coconut into a single layer on a baking sheet. Bake at 350° for 8 minutes or until lightly toasted, stirring every 2 minutes. Let cool 10 minutes. Stir toasted coconut; 1/2 cup cashews, chopped; and 2 Tbsp. finely chopped crystallized ginger into batter. Increase bake time to 44 to 46 minutes.
Test Kitchen Secret: Easy Topping Upgrades
For indulgent and family-friendly double-decker brownies, prepare So Good Brownies as directed through Step 3. Add a topping layer and adjust the baking times slightly.
Peanut Butter Streusel Brownies: Stir together 1/2 cup all-purpose flour, 2 Tbsp. light brown sugar, 2 Tbsp. granulated sugar, 1/3 cup chunky peanut butter, 2 Tbsp. melted butter, and 1/8 tsp. salt until blended and crumbly. Sprinkle peanut butter mixture over batter. Increase bake time to 50 to 54 minutes.
Candy-and-Pretzel Brownies: Sprinkle 1 cup pretzel sticks, broken into pieces, and 2 (3.7-oz.) king-size chocolate-coated caramel-peanut nougat bars, coarsely chopped, over batter. Increase bake time to 52 to 54 minutes.
Note: Be sure to insert wooden pick into brownies, not candy bar pieces, when testing for doneness. We tested with Snickers King Size candy bars.
Spicy Pecan Brownies: Whisk together 1 Tbsp. ancho chile powder, 2 Tbsp. maple syrup, 1/4 tsp. ground cinnamon, 1/8 tsp. salt, and 1/8 tsp. freshly cracked pepper in a medium bowl. Stir in 1 1/2 cups chopped pecans. Sprinkle pecan mixture over batter. Increase bake time to 42 to 46 minutes, shielding with aluminum foil during last 15 minutes of baking to prevent excessive browning, if necessary.