(adapted from Food Network Canada)
1 cup unsalted butter
3 ounces best-quality semisweet chocolate, finely chopped
1 cup white sugar
1/2 cup cocoa powder (sifted)
1/2 cup mascarpone cheese
3 large eggs, at room-temperature
2 teaspoons pure vanilla extract
1/2 cup all-purpose flour
1/2 teaspoon salt
6 ounces best-quality semisweet chocolate, finely chopped
6 tablespoons whipping cream
3 tablespoons unsalted butter
Preheat oven to 325F and grease or parchment paper an 8x8 pan. Set aside.
In glass mixing bowl melt butter in microwave on full power. Stir in chocolate and mix until combined (a few additional seconds in the microwave may be needed). Note: This may be done over a double boiler, but we've never seen why you should bother with the hassle!
Add sugar to chocolate/butter mixture until combined. Heat for an additional 30 seconds on high, remove and stir until it looks shiny. It will still look a bit grainy.
Add marscapone, vanilla, eggs and mixing until smooth.
Sift flour, salt and cocoa into mixture with a sieve and stir just until combined, making sure to scrape all sides of the bowl. (Mixture will be rather light in texture, instead of dense and heavy like many brownie batters)
Pour batter into prepared pan and smooth top to ensure even baking. Bake for 40-50 minutes until tester comes out almost clean.
Use the flat end of a potato masher to lightly tamp down the surface of the brownies while they are still warm. Do not squish, merely flatten any parts that might have raised more than others (typically the edges). This will help the ganache coat evenly. Leave in pan and set on wire rack to cool.
While brownies are cooling, make your ganache to pour over the top (which you will want to do while your brownies are still warm). To do so, simply heat butter and cream on medium power (taking care not to boil) in the microwave and add chocolate. Stir until all lumps disappear. Immediately pour over brownies. Let cool completely (we find placing them in the fridge helps up stay out of the pan until they the ganache is set 100%). Once chilled a knife will cut through them cleanly, make sure to clean your blade for each cut for a more polished look.
The mascarpone keeps things moist and dense without the same thin, underdone taste of a normal fudgy brownie. It also allows the chocolate to shine through without feeling a sugar coma after eating one (although we make no promises that you can eat just one).