Preheat your oven to 425°F (220°C) and line two baking sheets with parchment paper.

In a medium saucepan, bring 1 cup of water, ½ cup of unsalted butter, 1 tablespoon of granulated sugar, and a pinch of salt to a rolling boil over medium heat. Remove from heat and stir in 1 cup of all-purpose flour until smooth.

Allow to cool for a few minutes before mixing in four large eggs one at a time until glossy.

Transfer dough to a piping bag and pipe 1.5-inch rounds onto prepared sheets, smoothing tops. Bake for 10-12 minutes, then reduce temperature to 350°F (175°C) and bake an additional 18-20 minutes until golden brown.

In another saucepan, heat 1 cup of full-fat eggnog and ½ cup of whole milk until almost boiling. Mix ½ cup of granulated sugar and 3 tablespoons of cornstarch, whisk with 4 beaten egg yolks, and gradually add hot mixture.

Return to heat, stir until thick, then stir in 2 tablespoons of unsalted butter, 1 teaspoon of vanilla extract, ½ teaspoon of ground nutmeg, and a pinch of salt. Chill until ready to use.

Whip 1 cup of heavy cream with 2 tablespoons of powdered sugar until stiff peaks, then fold into the cooled eggnog pastry cream.

When cream puffs are cool, create a hole and pipe in eggnog filling until full, then dust tops with powdered sugar.