Quick & Easy Microwave Suet Pudding. And how does onion pudding factor into Kate's childhood, and her life as a parent today? Onion pudding is so simple to make, with just a few ingredients and the magic of a microwave, this satisfying hearty side dish can be prepared effortlessly alongside a roast dinner or Christmas lunch. No one I've ever talked to has ever heard of it though! Step 1. Without the lid, all that steam will escape and the pudding won’t cook properly all the way through. In a large bowl combine suet, raisins, corn syrup, water, baking soda, 1 teaspoon salt, nutmeg, cinnamon, cloves, flour and baking powder; mix well. popular in the North of England, but nobody I've ever mentioned it to has heard of it.