Preheat your oven to 350°F (175°C). Line an 8×8-inch baking pan with parchment paper, leaving overhang on two sides for easy removal. Lightly spray the parchment with non-stick spray.

Pro Tip: For thinner brownies with more edge pieces, use a 9×9-inch pan and reduce baking time by about 5 minutes.

In a large bowl, combine the cocoa powder and hot coffee (or water). Stir until smooth – you'll notice the mixture becomes fragrant and glossy. This process, called blooming, intensifies the chocolate flavor. Let it cool for 2 minutes while you gather the remaining ingredients.

Add the melted butter and oil to the bloomed cocoa mixture, whisking until combined.

Whisk in the sugar until fully incorporated – the mixture will look grainy but glossy.

Add eggs one at a time, whisking well after each addition until the batter becomes shiny and smooth.

Stir in the vanilla extract until just combined.

Visual Cue: Your batter should now be thick and glossy, like chocolate pudding.

In a separate bowl, whisk together the flour, baking powder, and salt.

Gently fold the dry ingredients into the wet mixture using a rubber spatula, stopping just when no dry streaks remain.

Fold in chocolate chips and/or nuts if using, being careful not to overmix.

Pro Tip: For the fudgiest brownies, count your strokes when folding in the dry ingredients. Aim for no more than 40-50 strokes total.

Pour the batter into your prepared pan, spreading it evenly into the corners with a spatula.

Tap the pan firmly against the counter 2-3 times to release any air bubbles.

Bake for 25-30 minutes, or until a toothpick inserted 1 inch from the edge comes out with a few moist crumbs attached.

Visual Cue: The top should be set and crackly, but the center should still seem slightly underdone. This ensures your brownies stay fudgy once cooled.

Allow the brownies to cool in the pan for 15 minutes.

Use the parchment paper overhang to carefully lift the brownies out of the pan and onto a cooling rack.

Let them cool completely (at least 1 hour) before cutting for clean slices.

For the cleanest cuts, refrigerate for 30 minutes before slicing with a sharp knife, wiping the blade clean between cuts.