Popovers, also known as Yorkshire pudding, rise tall and crisp on the outside with a soft, hollow center, no yeast or baking powder involved. Steam does all the work here, and a hot muffin tin is what gets them to puff up instead of falling flat. From mixing the batter to pulling them out of the oven is about an hour, most of it hands-off resting time.
In a bowl with a spout, combine eggs, milk, flour, salt and dry mustard and blend with a hand mixer until well combined. Let the batter sit for at least 30 minutes.
Preheat oven to 425º. Place 1 teaspoon oil in each hole of a 12 hole muffin tray. Place on top rack in the oven and bake until the oil is hot and almost smoking.
Remove pan and immediately pour equal portions of batter into the muffin tins. It should be hot enough that it sizzles. Quickly return to the oven and bake for 15-20 minutes, until they have risen and are golden brown. Do not open the oven while baking.
Serve immediately. They will fall a little once removed from the oven creating a hole in the center for butter or gravy.
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Barbara's Notes + Tips
Popovers are done when they're tall, deep golden brown, and firm to the touch, usually at the 15 to 20 minute mark.
These don't hold up well as leftovers, but if you have extras, store them airtight in the fridge for up to 2 days and reheat in a hot oven, not the microwave, to keep the outside crisp.
No muffin tin handy? Bake the same batter in a metal baking dish for a traditional single Yorkshire pudding, just watch the bake time since it'll run longer than individual portions.