Preheat Oven: Preheat oven to 350°F (175°C) and line an 8×8-inch pan with parchment paper.
Melt Chocolate & Butter: Melt butter and chopped chocolate together over low heat or in the microwave, then let it cool slightly.
Mix Sugars & Eggs: In a bowl, whisk brown sugar, granulated sugar, eggs, and vanilla until smooth and slightly thick.
Combine Chocolate Mixture: Add the cooled chocolate mixture to the egg mixture and mix until well combined.
Add Dry Ingredients: Add flour, cocoa powder, baking powder, and salt, then mix gently until just combined.
Fold Add-ins: Fold in chocolate chunks and sliced strawberries evenly into the batter.
Transfer to Pan: Spread the batter evenly into the prepared baking pan.
Top (Optional): Add extra strawberries and chocolate chunks on top for a bakery-style finish.
Bake Brownies: Bake for 25–30 minutes until edges are set and center remains slightly soft.
Cool Brownies: Let brownies cool completely in the pan before slicing.
Slice & Serve: Cut into squares and serve.