Preheat oven: 180°C / 160°C (fan) / Gas Mark 4 / 350°F
Heat the chocolate and butter in the microwave until melted and smooth.
Beat the eggs and sugar until fluffy and combined.
Add in the chocolate mixture to the egg mixture, then add in the orange extract and rum and stir until smooth.
Sieve in the flour, baking powder and cocoa powder, then add the cinnamon, nutmeg and salt, stirring together until just combined.
Stir in the chocolate chips until only just spread evenly throughout.
Using a tablespoon (or ¼ cup scoop), spoon the brownie mix onto a lined baking tray, leaving a few inches between scoops and bake for 10-12mins until risen and a papery texture on top.
Allow the brownie cookies to cool on the tray before moving them and enjoy!