Preheat your oven to 350°F (175°C) and grease an 8-inch square baking pan with butter or cooking spray, lining with parchment paper.

Melt 1 cup of unsalted butter in a microwave-safe bowl in 30-second intervals until warm, stirring after each interval.

Stir in 2 cups of granulated sugar, 4 large eggs, and 1 teaspoon of vanilla extract into the melted butter until smooth.

Sift together ¾ cup of unsweetened cocoa powder, 1 cup of all-purpose flour, ½ teaspoon of salt, and 1 teaspoon of baking powder. Slowly incorporate into the wet ingredients, stirring gently.

Fold in 1 cup of chocolate chips until evenly mixed throughout the batter.

Pour the brownie batter into the prepared baking pan, smoothing it into the corners with a spatula.

Bake in the preheated oven for 20 to 25 minutes, until a toothpick comes out with moist crumbs attached.

Remove the brownies from the oven and let them cool in the pan for 10 minutes before lifting out to cool completely on a wire rack.

Use a heart-shaped cookie cutter to cut the cooled brownies into shapes and arrange on a serving platter.