Why tequila for Christmas?
Aged anejo tequila spends months or years in oak, which gives it caramel, vanilla, and baking-spice notes, much closer to a spiced rum or a bourbon than to a bright blanco. That warmth is exactly what a holiday cocktail wants. Here it plays against the Irish cream and cinnamon like a cozy nightcap, so it feels festive without tasting like a margarita.
The cinnamon-sugar rim (the trick)
Rim the glass while your shaker is still frosty. Wet the rim with a little cream or a citrus wedge, then press it into a plate of cinnamon sugar (about two parts sugar to one part cinnamon). The cold helps the sugar grip, so you get a clean, even rim that dissolves slowly as you drink.
Cinnamon syrup, and what to swap
Cinnamon syrup is easy to buy, or make your own: simmer equal parts sugar and water with two or three cinnamon sticks for ten minutes, then cool and strain. No Irish cream on hand? Use a splash more cream plus a bar spoon of vanilla, or swap in a horchata cream for a Mexican twist that suits the tequila.
Serve it warm (optional)
For a hot version, gently warm the cream, cinnamon syrup, and a little extra Irish cream in a saucepan, take it off the heat, stir in the anejo (do not boil the alcohol off), and pour into a warmed mug. It becomes a cinnamon tequila nightcap for a cold night.
Make it for a party, and a pumpkin-spice twist
Batch the anejo, Irish cream, cinnamon syrup, and cream at the same ratio in a bottle and keep it cold; shake each serving over ice to order so it stays frothy. For a festive variation, swap the cinnamon syrup for pumpkin spice syrup, which turns it into a pumpkin-spice sleigh ride.
Non-alcoholic version
Skip the tequila and Irish cream, use a non-alcoholic cream liqueur or extra cream with vanilla, keep the cinnamon syrup and the rim, and you have a kid-friendly cinnamon cream that still feels like Christmas.