-
Preheat the oven to 425°F. Line a standard muffin pan with muffin papers; grease the insides of the papers.
-
To make the batter: In a medium-sized mixing bowl, beat together the butter, vegetable oil, and sugars until smooth.
-
Add the eggs, beating to combine and scraping the bottom and sides of the bowl if necessary.
-
Stir in the baking powder, baking soda, nutmeg, salt, and vanilla.
-
Add the flour alternately with the milk, beginning and ending with the flour and making sure everything is thoroughly combined. Scrape the sides and bottom of the bowl and mix for 30 seconds more.
-
Scoop the batter into the prepared pan, filling the cups nearly full.
-
To bake the cupcakes: Bake the cupcakes for 15 to 17 minutes, or until they're a pale golden brown and a toothpick or paring knife inserted into the middle of one of the center cupcakes comes out clean.
-
Remove the cupcakes from the oven and let them cool for a couple of minutes, or until you can handle them. Tip them out of the pan and place them on a rack.
-
While the cupcakes are still slightly warm, use a paring knife to cut a slit 1” wide and 1 1/2” deep in each. If you like, use a small measuring spoon (a 1/4 teaspoon works well) to scoop out some of each cupcake’s center. Let the cupcakes cool completely.
-
To finish the cupcakes: Use a pastry brush to coat the top of each cupcake with melted butter. Dip the tops in confectioners’ sugar, coating thoroughly. Note: If you dip them while still warm, the sugar will melt and the tops won’t stay white.
-
Place the jam in a pastry bag with a medium round tip. Squeeze the jam into the void you’ve created until it just comes out the top. Repeat until all the cupcakes are filled.
-
Storage information: Store cupcakes, covered securely, at room temperature for up to three days; freeze for longer storage.