Preparation

• Put the flour in a large glass measure with a spout or a large bowl. Make a well in the flour. In a medium bowl, whisk the milk and eggs. Gradually whisk the milk mixture into the flour until smooth. Whisk in the thyme, 2 tsp. salt, and 2 tsp. pepper. (Let the batter sit at room temperature, covered, for a half-hour or up to 24 hours refrigerated. Let cold batter sit at room temperature for a half-hour before baking.)
• Position a rack in the lower third of the oven and heat the oven to 425°F. Pour 1 tsp. of the vegetable oil into each of 12 nonstick popover cups or 24 muffin-tin cups. Put the tins on a rimmed baking sheet or sheets, transfer to the oven, and heat until quite hot, about 5 minutes.
• Remove the baking sheet from the oven and carefully pour the batter into the hot cups, dividing equally. Bake without opening the door until the popovers are puffed and golden brown, 20 to 25 minutes. Allow to cool slightly (they will collapse a bit) before removing from the tin. If some puddings stick, gently pry them out with a small offset spatula or butter knife. Serve immediately.