Preheat Oven & Prep Pan: Preheat your oven to 356ºF (180ºC). Line a 8x8 square baking pan with parchment paper and set aside.
Melt Butter: Melt the butter and let it cool for about 5 minutes, or until just warm.
Mix Wet Ingredients: In a large mixing bowl, combine the cooled melted butter, eggs, sugar, and vanilla. Beat on medium speed for 2 minutes until the mixture is well combined.
Incorporate Olive Oil: While mixing on low-medium speed, slowly drizzle in the olive oil, continuing to mix for about 1 minute to emulsify.
Add Dry Ingredients: Sift the flour and cocoa powder directly into the bowl. Add the salt. Mix on low-medium speed just until combined. Avoid over-mixing to maintain a fudgy texture.
Prepare the Batter: Pour the batter into the prepared baking pan, spreading out evenly.
Add Pumpkin Seeds: Sprinkle pumpkin seeds evenly over the top of the batter.
Bake: Place in the oven and bake for 18-22 minutes, or until a toothpick inserted in the center comes out with moist crumbs. This slight under-baking helps achieve a fudgy texture.
Cool: Remove from the oven and let the brownies cool in the tin for 10 minutes. Then, using the edges of the parchment paper, lift the brownies from the tin and transfer to a wire rack to cool completely.
Serve: Once cooled, cut into squares and serve. Enjoy!