Preheat oven to 350 F. Spray an 8-inch square baking pan with non-stick cooking spray, set aside. Using a double boiler, or a medium heatproof bowl set over a pan of almost simmering water, melt the chocolate and butter, stirring occasionally until smooth (see [tips for melting chocolate|https://www.ifyougiveablondeakitchen.com/2013/12/02/tips-for-melting-chocolate/]). Whisk in the cocoa. Set aside to cool. Whisk together the eggs, sugar, vanilla and salt in a medium bowl until combined, about 30 seconds. Whisk the warm chocolate mixture into the egg mixture, then stir in the flour with a wooden spoon until just combined. Pour the mixture into the prepared pan, spread into the corners and level with a offset spatula. Bake 35 to 40 minutes, or until slightly puffed and a toothpick inserted into the center comes out with a small amount of sticky crumbs clinging to it. Cool on a wire rack to room temperature, about 2 hours. When the brownies are completely cooled, spread the strawberries evenly over the brownies. Melt the chocolate chips and shortening together in a double boiler or microwave at 50% power level (refer to [tips for melting chocolate|https://www.ifyougiveablondeakitchen.com/2013/12/02/tips-for-melting-chocolate/]). Pour evenly over the strawberries. Refrigerate for at least 1 hour. When ready to serve, cut brownies into one-inch squares.