Summarize the following:
Melt 2-3 tablespoons of butter and whisk it into the batter with the milk and eggs for a rich, buttery popover. Let the butter cool slightly after melting it – otherwise it might cook the eggs slightly. Simply sprinkle shredded cheese, such as gruyere or cheddar, on top of the batter before it goes in the oven, then cook normally. The final popover will by topped with crispy, delicious cheese. Simply add 1-2 tablespoons of sugar with the flour and whisk it into the batter, then add whatever other sweet ingredients your heart desires. Some ideas include:  ½ teaspoon vanilla extract and 2 teaspoons orange zest ½ teaspoon vanilla and 1 ounce chopped semisweet chocolate.  Brush the tops of cooked popovers with melted butter, then sprinkle with ground cinnamon and sugar. Popovers are a fantastic addition to dinners in place of rolls or bread, and can be customized to fit your meal. Try mixing and matching the following variations, adding them to your batter with the flour:  ¼ cup chives, chopped finely ¼ cup roasted shallots or garlic, chopped finely  1 teaspoon rosemary, thyme, or basil, minced 4 pieces cooked bacon, finely chopped

Summary:
Add melted butter for a richer pastry. Top your popovers with shredded cheese before cooking. Try sweet popover recipes. Try out savory popover recipes.