In a small saucepan, combine raspberries, sugar, and a splash of water over medium heat. Stir gently until saucy, then mash with a fork. Boil for 2 minutes, strain, and let cool.

Preheat your oven to 350°F (175°C) and line a 9x9 inch baking pan with parchment paper.

In a saucepan over low heat, combine semi-sweet chocolate chips and butter. Stir continuously until melted and smooth, about 5 minutes. Let cool slightly.

In a mixing bowl, whisk together room-temperature eggs, sugar, and vanilla until well combined. Gradually add to cooled chocolate mixture, stirring until glossy.

Fold in flour, baking powder, and baking soda. Mix gently until just combined to keep brownies fudgy.

Pour the brownie batter into the prepared baking pan. Drop spoonfuls of raspberry sauce over and swirl with a knife.

Bake in the preheated oven for 30 minutes. A toothpick should come out with a few moist crumbs for the perfect texture.

Allow brownies to cool completely in the pan for about 1-2 hours before slicing.