• Prepare the batter: In a medium bowl, whisk together the eggs, flour, milk, water, and salt until smooth. Let the batter rest at room temperature for at least 30 minutes, or refrigerate it overnight for the best results.
• Preheat the oven and pans: Adjust your oven rack to the center position and preheat the oven to 450°F (230°C). Divide the drippings or oil evenly between two 8-inch cast iron skillets, popover tins, or a muffin tin. Preheat the pans in the oven until the fat is smoking hot, about 10 minutes.
• Bake the puddings: Carefully remove the hot pans from the oven and place them on a heat-proof surface. Divide the batter evenly between the wells, filling them about halfway. Immediately return the pans to the oven and bake until the puddings have quadrupled in volume, are deep brown, and crisp to the touch, about 15 minutes for smaller tins and 25 minutes for larger pans.

Serve

• Serve the Yorkshire puddings immediately while they’re hot and crisp. They can be cooled, transferred to a freezer bag, and frozen for up to three months. Reheat in a hot toaster oven before serving.