1. COMBINE the butter, chocolate, brown sugar and chipotle in a saucepan and stir over a medium heat until melted and smooth. Remove from heat and stand for 1 hour. Remove the chipotle and discard.
2. WHISK in the eggs, add the sifted flour, cocoa, cinnamon, salt and baking powder and stir until well combined. Pour into a greased and base lined 28cm x 18cm slice pan.
3. BAKE in a moderate oven 180°C for 30 minutes or until cooked. Cool in pan on a wire rack before cutting. Cut into squares and sandwich together with a scoop of chocolate ice cream. Serve with a drizzle of chocolate sauce, and a sprinkle of cayenne on the serving plate for some extra heat and spice if desired.
TIP: Chipotles are smoked and dried jalapeno chilies.