Rich Chocolate Cake - cooking recipe

Ingredients

3 ounces unsweetened chocolate, finely chopped (good quality)
2 cups all-purpose flour
1/4 cup cornstarch
1 1/2 teaspoons baking soda
1/2 teaspoon salt
1 1/2 cups light brown sugar (firmly packed)
8 tablespoons unsalted butter, softened
1 cup sour cream, at room temperature
3 eggs, lightly beaten,at room temperature
1 teaspoon vanilla extract
1 cup water

Preparation

Position a rack in lower third of oven and preheat to 350F.
Line the bottoms of two 9x2-inch round pans with parchment paper.
Melt chocolate in microwave (LOW or MED), stirring occasionally until smooth.
You may use a double boiler too (make sure water is HOT, not simmering).
Cool chocolate until tepid.
Sift flour, cornstarch, baking soda and salt into a large mixing bowl.
Add brown sugar.
Using a paddle blade on electric mixer, combine the ingredients on low speed.
Add butter and sour cream.
Mix on med-low speed for 1 min to make a thick batter.
Add eggs, melted chocolate and vanilla.
Increase speed to high and beat for 2 mins.
Stop and scrape down the bowl.
Resume mixing at med-high, for about 5 sec.
Reduce speed to low and slowly pour in the water just until thoroughly blended.
Spoon batter into prepared pans and spread it evenly.
Bake until tops spring back when pressed lightly in the centers and a toothpick inserted into the centers comes out clean, 30-35 mins.
Transfer to cooling racks and cool for 10 mins.
Invert onto racks and remove pans.
Peel off the parchment and cool the cakes right side up.
NOTE: The cake can be baked 1 day in advance.
Wrap the cooled cake layers tightly with plastic wrap to store.
Or to freeze, over-wrapped with foil, for up to 2 weeks.