Here is my basic popover recipe:
2 tablespoons solid fat (butter or animal fat (duck fat, mmm) or solid shortening)
3 large eggs, at room temperature
1 cup (250 ml) whole milk, at room temperature
1 teaspoon salt
1 1/2 teaspoons sugar
1 cup (140 g) all purpose or white whole wheat flour
1 tablespoon vital wheat gluten
This tactic assumes you own a wand blender and a wide-mouthed quart Mason jar and a microwave. If not, just make the popovers the way you normally would--or if you are missing the wand blender but have a normal blender, you can melt the butter in a different container and use the normal blender.
About an hour or two before dinner, take your Mason jar. Put the butter/whatever in it. Put it in the microwave and melt it. (If you are making Yorkshire pud and are waiting for the roast to be finished before you add the fat, skip this step for now, and stir the fat in before you bake the popovers.)
Add the milk, eggs, salt, and sugar to the butter in the Mason jar (or blender)(or just put them in the blender if you are adding the fat later). Do not put the eggs directly into the hot butter before diluting it with the milk. Otherwise you will have scrambled eggs, which are nice, but not popovers.
Whiz them all up with the wand blender.
Add the flour and the wheat gluten.
Whiz that too, until you have a nice smooth batter.
Let the batter sit on the counter until dinner is nearly ready. If you are roasting something at 400 degrees, you're good; otherwise preheat your oven to 400 (F). (200 C)
Liberally grease 9 cups of a 12-cup muffin tin, or if you are making Yorkshire pud, drizzle a little of the fat from the roast into the bottom of the cups. If you have one of the giant-sized six muffin muffin tins, then you will have bigger popovers and they need to bake a little longer.
Using silicon cups for this results in popovers without stumps or a lot of loft, as they just levitate themselves out of the super-slick cups entirely. They still taste good!
If you are using fat from the roast you're making, add it now and stir it in.
Divide the popover batter between the nine greased cups. You can just pour it from the blender or the Mason Jar.
Stick in oven. Do not peek! If you open the door before they are set, they won't rise properly.
Bake for 35 minutes or until deep mahogany brown.
Pull pan from oven. Tilt popovers in cups, or remove them to a rack or basket. Pierce each one with a bamboo skewer. (careful of the steam!) The purpose of these two procedures is to (a) prevent them from getting soggy and (b) prevent them from collapsing.
However you meant to eat them. Do not plan on leftovers.
Wash your one. dirty. dish. Oh, and the wand blender, sure. And the muffin tin. But that was inevitable.
ETA: Nota Bene
For even more loft in your popovers, preheat the muffin tin with the grease in it in the 400-degree oven for a few minutes before pouring the batter in. This is a bit tricky, though, and can be skipped.