Preheat the oven to 350°F. Line an 8x8-inch pan with parchment paper or lightly grease with cooking spray.
Melt butter in a large saucepan. Add sugar and vanilla extract, stirring until combined. Remove from heat. Whisk in cocoa powder, sea salt, and eggs. Whisk in the flour, stirring until smooth. Pour into baking pan and bake 25-30 minutes or until a toothpick comes out clean. Let cool completely.
Once the brownies are completely cool, lay the sliced strawberries in a single layer on top.
Place the semisweet chocolate in a heatproof bowl over a pan of simmering water. Stir the chocolate until it completely melts. Remove from the heat and pour the chocolate over the strawberries. Spread evenly, being careful not to move the strawberries around.
Chill in the refrigerator until the chocolate layer hardens, about 10-15 minutes. Let sit at room temperature for a few minutes before serving. (Can be stored for up to a week in an airtight container in the refrigerator.)