S'mores brownies with toasted marshmallows

Ingredients

• 175 g unsalted butter for firm (or 220 g for fudgy)
• 50 g cocoa powder
• 200 g 70% dark chocolate
• 3 tbsp oil
• 1 shot espresso (or 1 tbsp instant coffee)
• 3 eggs
• 100 g brown sugar
• 190 g powdered sugar
• 66 g all-purpose flour
• 1 tbsp vanilla
• Pinch of salt
• 180 g milk or semisweet chocolate, chopped
• 150 g Graham crackers
• 150 g marshmallows

Instructions

1. Line the pan and lay down a full layer of Graham crackers.
2. Melt the butter with the dark chocolate and oil, whisk in the cocoa and coffee.
3. Whisk the eggs with both sugars and vanilla until pale, stream in the chocolate mixture, then fold in the flour, salt and chopped chocolate.
4. Pour the batter over the crackers and bake at 180°C (350°F) for 30 minutes.
5. Top with the marshmallows and broil 1–2 minutes, until blistered and golden.
6. Cool 1 hour before cutting — the marshmallow layer needs to set.