1. Spoon jam or currants into the bottom of a greased six-cup-capacity pudding basin.
2. Put cake mix, water, eggs and butter into an electric mixer bowl. Mix at low speed until the ingredients are combined. Beat for 2 minutes at medium speed. Scrape down sides of bowl occasionally.
3. Spoon mixture into prepared basin. Cover with pleated greaseproof paper. Secure with string.
4. Steam for 1¼ hours or until pudding feels firm to touch.
5. Unmold onto a serving plate. Serve hot with Edmonds custard.