Place an oven rack in the middle position of your oven. Preheat the oven to 425 degrees F. In a bowl, beat the eggs until well blended. Mix in the milk, water, salt, pepper and nutmeg. Whisk in the flour until just combined; it’s okay if there are a few lumps. Thoroughly grease two, 12-slot non-stick mini muffin pans with vegetable oil spray. Pour in the batter, filling each slot to the top. Bake for 10 minutes. Reduce the heat to 325 degrees F and bake 20 to 25 minutes more, or until the Yorkshire puddings are puffed and golden. Set the pans on a baking rack and cool for 5 minutes. Carefully remove the Yorkshire puddings from the pans and set on a baking sheet. Can be made several hours in advance. Cool to room temperature, and then cover and reserve until ready to reheat in the oven for a few minutes. Serve alongside roast beef.