Preheat your oven to 350F. Line an 8x8 brownie pan with parchment paper and set aside.
In a bowl, mix all dry ingredients and set aside. In a separate heatproof glass bowl, add chocolate chips and butter. Microwave on high heat for 1 minute 20 seconds. If you don't have a microwave, you can melt your chocolate over a double boiler.
Add your vanilla extract sugar and whisk until completely dissolved. Add your eggs, one at a time and whisk continuously until well combined. Add dry mixture and gently fold it in until well combined. Pour your batter onto your brownie pan and using a spatula, make sure that your brownie batter is evenly spread.
(OPTIONAL) drop 2 tbsp of dulce de leche onto your brownie batter and using a chop stick, swirl around your dulce de leche until you get a marbled texture.
Bake for 20-22 minutes for a super fudgy brownie, and a little more (25 minutes max) if you want your brownie to be a little more set. Take your brownie pan out, and let it completely cool down for at least an hour (2 hours for best results). Serve and enjoy!