A friend of mine has just lent me the cookbook from Tartine, another well known San Francisco Bakery&Cafe. She advised me that the brownies are the best ever. She is american so we can trust her 100%...
Brownies, adapted from Tartine
3/4 cup unsalted butter (170gr)
1 pound bittersweet chocolate, coarsely chopped (455gr)
3/4 cup + 2 tbs all-purpose flour (130gr)
5 large eggs
2 cups light brown sugar (395gr)
1/2 tsp salt (2ml)
1 tsp vanilla extract (5ml)
1. Preheat the oven to 350F. Butter a 9-by-13-inch glass baking dish.
2. In a small saucepan, melt the butter over low heat. Remove from the heat and add the chocolate. If the heat from the butter does not fully melt the chocolate, put the pan back over the heat for 10 seconds and stir until melted. Set aside to cool.
3. Sift the flour into a small mixing bowl. Set aside. In a medium mixing bowl, combine the eggs, sugar, salt, and vanilla. Using a mixer fitted with the whisk attachment, beat on high speed until the mixture thickens and become pale in color and falls from the whisk in a wide ribbon. Using a rubber spatula. fold the cooled chocolate into the egg mixture. Add the flour and fold it quickly but gently with the rubber spatula so that you don't deflate the air that's been incorporated into the eggs.
4. Pour the batter into the prepared dish and smooth the top with the spatula. Bake until the top looks slightly cracked and feels soft to the touch, about 25 minutes. Let cool completely on a wire rack.
5. Use a sharp knife, cut into 12 squares, or size desired. The brownies will keep in an airtight container in a cool place for up to 1 week.
NB: You can't use a cake tester to judge doneness for these brownies. Because the batter has a high percentage of chocolate, the tester comes out wet even if the brownies are done.
Very chocolaty, very "fudgy", very good. "Decadent" as my friend says!