Preheat oven to 350°F. Line a square 9x9-inch baking dish with a parchment paper sling or spray with baking spray.
In a large microwave-safe bowl, combine the bittersweet chocolate and butter. Microwave on high in 20-30 second bursts, stirring well between bursts of heat until melted and smooth. Whisk in the cocoa powder.
¾ cup (170g) salted butter, 4 ounces bittersweet chocolate, ½ cup (43g) unsweetened cocoa powder
Add the granulated sugar, whisking well to combine. Add the eggs and vanilla extract, beating well either by hand with a whisk or using a hand mixer.
1 ½ cups (300g) granulated sugar, 2 teaspoons pure vanilla extract, 3 large eggs
Sprinkle the flour and salt over the brownie batter and gently stir it in with a wooden spoon or spatula. Stir in the chocolate chips.
¾ cup (95g) all-purpose flour, ½ teaspoon salt, ¾ cup semisweet chocolate chips
Pour the brownie batter into the prepared baking dish and spread into the corners.
Bake for 30 to 35 minutes, until a toothpick inserted into the center of the brownies comes out mostly clean with only a few crumbs attached. Be sure not to overbake.
Cool completely. Arrange strawberries halves on top of the brownies spaced close together with cut sides down.
2 cups halved strawberries
Heat heavy cream in a small saucepan on the stovetop or in the microwave for 1-2 minutes just until bubbles start to appear around the edges of the pan. Do not boil. Pour over the chocolate chips in a medium bowl and let sit for 5 minutes without stirring. Stir until smooth and combined, then pour over the strawberries and brownies. Refrigerate for 2-3 hours until set, then slice and serve.
1 cup heavy cream, 2 ⅓ cups semisweet chocolate chips