To make the popovers, in a blender, combine the eggs, milk, flour, sugar, and salt. Blend on high speed until smooth, about 30 seconds. Scrape down the sides of the blender and add the melted butter. Blend on high until combined, about 10 seconds. Add the poppy seeds and pulse once or twice to combine. Set aside for 15 minutes for the batter to rest.
Position a rack in the lower third o