Step 1Grease a 1 1/2-quart pudding mold with butter. Set aside.
Step 2Combine the currants, almonds, raisins, candied citron and candied lemon and orange peels in a bowl. Coat with 1/4 cup of flour. Add the beef fat trimmings and mix again. Set aside.
Step 3In a separate bowl, beat the egg yolks until smooth. In another bowl, beat the egg whites until stiff.
Step 4Dissolve the baking soda in cold water.
Step 5In a large mixing bowl, cream the butter and sugar by beating until light and fluffy. Add the beaten egg yolks. Stir in the milk, then stir in the stiff egg whites alternately with the remaining 1 3/4 cups flour. Add the cinnamon, cloves, salt, nutmeg, orange juice, lemon juice and dissolved baking soda. Stir in the flour-coated fruit mixture.
Step 6Fill the mold with the pudding and cover tightly. Set the mold in a pot and add boiling water until it comes halfway up the sides of the mold. Keep the water at a simmer, adding more as needed, 3 hours.
Step 7Let the pudding cool, turn it out of the mold, decorate it with sprigs of holly and serve with Hard Sauce.