Heat oven to 350°F. Line a 9×9″ metal pan with parchment, leaving a 1″ overhang. Spray lightly with cooking spray.

Whisk oil, melted butter, ⅔ cup stout and sugar until glossy. Add eggs and vanilla; whisk until smooth.

In another bowl, sift flour, baking powder, salt, Dutch cocoa and natural cocoa.

Gently fold the dry mix into the wet just to incorporate. Stir in chocolate chunks.

Transfer batter to pan. Bake 30–35 minutes for gooey centers or 35–40 minutes for firmer edges.

Place chips in a bowl. Heat cream + ¼ cup stout until steaming (1½ minutes), pour over chips, let rest 2 minutes, then whisk until silky.

Chill ganache 15–20 minutes, then whip with a hand mixer until light. Spread over fully cooled brownies.

Slice into squares and enjoy.