Preheat oven to 350°. Line a 9” sealed loose bottom cake pan.
Rub the margarine into the cake tin & sprinkle over the sugar evenly. Peel, cut mandarins into 3 pieces each. Lay them cut side down into the cake tin, fill any gaps with quarters or halves. Set aside while you make the cake.
In a medium size bowl, combine all the wet ingredients together.
In a large mixing bowl add the dry ingredients and mix well. Pour in the wet ingredients and stir lightly.
Once the mix has combined, pour it into the cake tin and give it a little tap on the surface to remove any air pockets.
Bake for 25-35 minutes, until cake tester comes out clean.
Once the cake has cooked, allow it to slightly cool for 5-10 minutes before removing it from the tin.
Before serving, glaze the cake with melted marmalade. Just add a couple tablespoons of water to loosen it. Garnish with fresh mint leaves.