This is another recipe where there are several different things with the same name. The traditional version (from at least the 18th century) which has biscuit crumbs, raisins, fat, sugar and egg mixed together then fried. There is a modern version which is completely different and has apricots and meringue on a puff pastry base.
Since I usually try to make the more authentic or historic version of a recipe, I had a go at the biscuit version.
Oxford Pudding, 'The Art of Cookery, Made Plain and Easy', Hannah Glasse (1747)
A quarter of a pound of biscuit grated, a quarter of a pound of currants clean washed and picked, a quarter of a pound of suet shred small, half a large spoonful of powder-sugar, a very little salt, and some grated nutmeg; mix all well together, then take two yolks of eggs, and make it up in balls as big as a turkey's egg. Fry them in fresh butter of a fine light brown; for sauce have melted butter and sugar, with a little sack or white wine. You must mind to keep the pan shaking about, that they may be all of a fine light brown.
I followed the above recipe fairly closely, using a generous heaped teaspoon of mixed spice instead of the nutmeg. The mixture was quite soft and the balls of 'pudding' collaposed slightly in the pan.
I let them cool for a couple of minutes before trying one. They were a bit like a bread and butter pudding bite, surprisingly soft despite the biscuits being quite hard. Since the recipe didn't mention the type of biscuits required, I used a mixture of spare/broken biscuits including oat cookies and shortbread.
After I had made my version, I found another recipe:
Oxford Dumplings, The Art Of Cookery (Mollard 1836)
Mix together a quarter of a pound of grated stale bread crumbs, a few currants, a little moist sugar, and a quarter of a pound of beef suet chopped fine, with two eggs, a little salt, and half a gill of cream. Divide the mixture into several parts and boil.
This version is much closer to a bread and butter pudding, using bread instead of biscuit and using a custard to bind everything together.