Preheat your oven to 375°F (190°C). Butter 4 ramekins and coat them with granulated sugar.

Whisk together eggnog, cornstarch, 1 tablespoon sugar, nutmeg, and cinnamon in a medium saucepan over medium heat until slightly thickened (3-5 minutes).

Stir in butter and vanilla extract after removing from heat. Let cool briefly, then whisk in egg yolks one at a time.

Beat egg whites until soft peaks form; gradually add remaining sugar and beat until stiff peaks form.

Fold one-third of the whipped egg whites into the eggnog mixture, then gently incorporate the rest.

Divide the mixture evenly among prepared ramekins and place on a baking sheet.

Bake soufflés for 13-15 minutes until puffed and golden, avoiding opening the oven door mid-bake.

Dust with powdered sugar before serving. Enjoy warm!