To make the simple syrup, bring the water to a boil in a small saucepan or pot.

Add the sugar and cinnamon to the water, stirring constantly until it dissolves.

Remove from heat and allow to slightly cool.

Pour 1/2 cup of apple cider and 1 cup of brut into 4 champagne glasses. Spoon the cinnamon simple syrup evenly into each glass.

Serve with stirrers, as the syrup tends to fall to the bottom of the glass.