Heat oven to 325 degrees F. Butter an 8-inch square Pyrex pan.
Place chopped chocolate in a mixing bowl; set aside.
In a small glass bowl, melt butter in microwave (take it out before it begins
Pour butter over the chocolate and let stand for 30 seconds. Stir until
chocolate is completely melted.
Sift in sugar and cocoa powder.
With a wooden spoon, beat in mascarpone, eggs and vanilla extract, mixing until
smooth. Gently fold in flour and salt.
Pour batter into prepared pan and spread evenly.
Place into preheated oven and
bake 45 to 50 minutes, or until a tester comes out clean.
Place pan on cooling rack and let brownies cool 10 to 15 minutes while you make
Place chopped chocolate in a mixing bowl.
In a small saucepan, bring the cream and butter to just below boiling point,
over medium heat. Pour this hot mixture over the chocolate and let stand for 30
seconds, then stir until smooth. Pour ganache over brownies while still warm, and
spread to cover evenly.
Let ganache firm up before cutting. It's best to refrigerate them until quite
Once the ganache is firm and the brownies have been cut, they do not need
to be kept in the refrigerator.