Position oven rack in lower third of oven. Preheat the oven to 450°F.
Place 1 teaspoon of the butter in each cup of a 6-cup standard popover pan. Place pan in oven and heat 3 to 5 minutes to melt the butter and preheat the pan.
Meanwhile, in a medium bowl, vigorously whisk together milk and eggs until frothy, about 1 minute. Melt 1 tablespoon of the remaining butter in medium bowl; add flour, salt, and vanilla. Whisk just until blended. (It's OK if there are small lumps.)
Carefully remove the popover pan from oven and swirl butter around cups to grease the pan. Divide batter evenly between cups, filling them 3/4 of the way full. Press 1 cube of cream cheese into center of each popover.
Bake 20 minutes. Lower oven temperature to 350°F. Bake 15 to 18 minutes longer, until puffed, golden and crisp.
Heat remaining 6 tablespoons of the butter in small skillet on medium heat. Allow the butter to brown until it smells toasted and is a deep golden color, about 3 to 4 minutes. Remove from heat and transfer butter to a heat-proof bowl. Mix sugar and cinnamon in a separate shallow bowl.
Brush each warm popover with browned butter, then roll (generously) in cinnamon sugar mixture. Enjoy warm.
•To store leftovers, place in an airtight container for up to 4 days at room temperature.
•To bring eggs to room temperature, place eggs in medium bowl and fill with warm water. Let stand 5 minutes.
•To make this recipe gluten-free, use an equal amount of your favorite gluten-free flour blend in place of the all-purpose flour.
•Want to make 12 mini popovers? Use a 12-cup muffin pan, instead of a 6-cup popover pan, with a few recipe modifications. Prepare as directed, but you’ll need 12 teaspoons of butter to grease the cups, and cut the cream cheese into 12 cubes instead of 6. Bake only 15 to 18 minutes in a preheated 450°F oven.