I don't really remember where I first found this idea, but it's another one of those post-holiday treats you can make with leftovers. This is usually where our holiday dinner goes, but you can put pretty much anything in this batter and it will taste good.
First, I preheated my oven to 400 degrees, heated up about two cups of diced leftover beef, veggies and gravy all mixed together and put our 10" cast iron skillet to preheat on the stove with a tablespoon of oil.
I got out three identical clear glasses, three eggs, milk and flour.
Yorkshire puddings are a traditional accompaniment to a Roast Beef dinner in the UK, and the recipes have been around for so long that they defy traditional measurements. Therefore, I set Sparky - who took a break from building his catapult (because what else does a boy do on vacation?) - to measure his ingredients in the traditional British way:
Sparky cracked 3 eggs into the first glass (this will make a pudding that will fill a 10" skillet, add more eggs for a larger cooking vessel)
Using the volume of eggs as a guide, in the second glass, he poured an equal volume of milk,
and in the third glass, he scooped an equal volume of flour as of milk or eggs (is it portentous that we wound up with three half-full glasses?)
These were tossed into the blender in that order (egg, milk, flour) and blended well.
I poured a tiny amount on the bottom of the now-sizzling skillet, topped it with my leftovers, and we poured the remaining batter over the top until our leftovers were swimming in it. Then we popped the whole thing into the oven, where it stayed until the top of the pudding was puffy and golden brown, about 10-15 minutes. (You can also use a square glass baking dish, but oil it well and put it in the oven as you preheat.)
We waited until it had cooled down a bit, (it will pouf in the oven, and then fall a bit like a souffle) then sliced it into wedges and ate it all up - and I think we almost enjoyed leftovers better than the dinner itself! Enjoy!