01 - Preheat oven to 350°F. Line an 8-inch square baking pan with parchment paper, leaving enough overhang on two sides to lift the brownies out later.
02 - Set a heatproof bowl over a saucepan of barely simmering water. Add the butter and chopped dark chocolate, stirring gently until completely melted and smooth. Remove from heat and let cool slightly for 2–3 minutes.
03 - Whisk the sugar into the melted chocolate mixture until well incorporated. Beat in the eggs one at a time, mixing thoroughly after each addition. Stir in the vanilla extract.
04 - Gently fold the flour and salt into the batter using a spatula, mixing only until just combined. Avoid overmixing to keep the brownies tender and fudgy.
05 - Pour the batter into the prepared pan and spread into an even layer. Bake for 25–30 minutes, or until a toothpick inserted in the center comes out with moist crumbs attached. Do not overbake. Let cool completely in the pan on a wire rack.
06 - Arrange the thinly sliced strawberries in an even layer across the fully cooled brownie surface, covering it completely.
07 - Melt the semisweet chocolate chips and coconut oil (or butter) together in a heatproof bowl set over simmering water, stirring until glossy and smooth.
08 - Pour the melted chocolate over the strawberry layer, spreading gently with a spatula to cover evenly. Refrigerate the pan for at least 1 hour, or until the chocolate coating is fully set and firm.
09 - Lift the brownies from the pan using the parchment paper overhang. Cut into 12 squares using a sharp knife warmed under hot water and dried for clean, neat edges. Serve chilled or at room temperature.