Preheat oven to 350ºF. Line 12-count cupcake tin with silicone or foil cupcake liners.
In a small bowl whisk together dry ingredients: almond flour, sweetener, baking powder, and xanthan gum. Set aside.
In a medium bowl, beat eggs with a whisk for one minute. Add vanilla and whisk. Make sure your melted butter is slightly cooled, and while continuing to whisk, stream it into the eggs.
Add the dry ingredients to the bowl of wet ingredients, and, using a spatula, stir together until well-combined. Add the vinegar and fold in.
Divide batter evenly among the 12 cupcake cups, and bake about 25 minutes. They are finished when the middle has firmed up and looks glossy. Remove and let cool completely.
Add a Keto frosting, and enjoy!
Note
For a twist on the flavor, use ½ teaspoon almond extract.
Cupcakes keep for 2 days in a tight, air-sealed container.