Fill a large pot 3/4 of the way full of water, cover it, and set it on the stove to boil.
Meanwhile, in a large bowl, combine flour, sugar, nutmeg, ginger, cloves, and salt.
Add mashed potato and mix until thoroughly combined.
Add raisins and currants and mix until evenly distributed.
In another bowl, beat the eggs until smooth, then stir in the milk.
Submerge your prepared muslin in the pot of boiling water. Remove the cloth from the water and wring out the excess moisture.
Flour the cloth, place the batter in the middle, then submerge and boil for four hours.
Lift the cloth out of the water and place it in a colander. Let sit 20 minutes before serving.