Soy Milk for Dairy Free Yorkshire Pudding

I'm always baffled about how substitutes work in recipes, and let's face it, most people - even cooks - haven't tried most substitutes in most recipes so they won't know either.

Gholam Rahman's food column at PalmBeachPost.com takes a stab at an unusual recipe request. I think she comes through okay, but I thought I'd repeat it here to see what people think.

Question: My niece is allergic to dairy products. Can I make Yorkshire pudding without milk, substituting maybe chicken broth? Thanks for your help. — Ann G., via e-mail

Answer: Originating in the Yorkshire region in the north of England, the pudding was originally made in the fat drippings from a roast beef and then served with gravy as part of the roast beef dinner. Mostly crust, it is raised by steam and eggs in a very hot oven, much like its American cousin, the popover.

Although milk plays a part in the puffing up of the batter, I don't think its role is critical. But there are better choices than chicken broth. I don't know if lactose intolerance is the cause of your niece's problem with dairy. If so, you can most likely use lactose-free milk, of which some brands are 100 percent free of lactose. These are real milk and will act just like milk although they are fat-free. You will have enough fat anyway in a Yorkshire pudding recipe. Otherwise, soy milk should also work in your recipe. Check with her doctor first, though.

When you tinker with a recipe, it is a good idea to follow the rest of the instructions carefully. Measure the ingredients accurately; preheat the oven to the desired degree, hot in this case and generally 425°; beat the batter smoothly and allow it to rest for a while, beating again to take any lumps out; and don't open the oven in the middle of baking or they likely will fall.