1. Melt the margarine and sugar in a saucepan
2. Mix the zest, orange juice and water into a jug and add to step one
3. Sift the flour, cocoa, baking powder together into a mixing bowl
4. Slowly add the liquids ingredients to the dry ones while stirring constantly. Add water if too dry.
5. Place into lined tins and bake in the oven at 180(Celcius) for 30 minutes.