3 ounces unsweetened chocolate, coarsely chopped
2 ounces bittersweet chocolate, coarsely chopped
1 cup all-purpose flour
1/8 teaspoon salt
12 tablespoon unsalted butter, softened
1 1/2 cups granulated sugar
2 large eggs (at room temperature)
1 1/2 teaspoons vanilla extract
1 1/4 cups sweetened shredded coconut

Position a rack in the center of the oven and preheat to 350 degrees F. Butter a 13 x 9-inch baking pan. Dust the pan with flour and tap out the excess. Melt chocolate together.

In a small bowl, using a wire whisk, stir together the flour and salt.

In a large bowl, using a hand-held electric mixer set at medium speed, beat the butter and sugar for 2 to 3 minutes, until the mixture is light in color and texture. Scrape down the side of the bowl with a rubber spatula. Beat in the eggs one at a time, beating well after each addition. Beat in the vanilla extract, then beat in the melted chocolate.

At low speed, beat in the flour mixture in two additions, scraping down the side of the bowl after each addition. Using a wooden spoon, stir in the coconut. Scrape the batter into the prepared pan and smooth the top with the rubber spatula. Bake for 25 to 30 minutes or until a wooden pick inserted in the center comes out with a few moist crumbs clinging to it. Do not overbake. Cool the brownies completely in the pan on a wire rack.

Using a large sharp knife, cut brownies lengthwise into 4 strips, then cut each strip into 5 pieces, to make 20 squares. The brownies can be stored in an airtight container at room temperature for up to 3 days.