Preheat oven to 350℉. Grease an 8x8 baking pan with butter and dust it with cocoa powder to help prevent the brownies from sticking. Set pan aside.
In a large microwave-safe bowl, melt 1 cup of butter. Add white and brown sugars. Using a whisk or electric hand mixer on medium speed, beat for 2 minutes.
Add eggs and vanilla. Beat again for 1-2 minutes to thoroughly combine the ingredients.
Using a mixing spoon, stir in cocoa powder and flour, being careful not to over mix. Stir until just combined.
Fold in chocolate chips and pour batter into prepared baking pan. Bake in preheated oven for 35-40 minutes.
While your brownies are cooking, beat together the remaining ½ cup of butter, powdered sugar, and strawberry jam/ jelly until smooth.
Remove brownies from the oven and let them cool in the pan on a wire rack. Pour frosting over the cool brownies, then use an offset spatula to spread it into an even layer. Transfer to the refrigerator to chill until the frosting sets.
Notes
Use unsalted butter instead - Use unsalted butter if you don’t have salted butter, just make sure you add ¼ teaspoon of Kosher or sea salt to the recipe as well.
For thinner brownies, use a 9x13 pan. You may need need to double the frosting to ensure you have enough to cover the entire brownie surface.