1/2 teaspoon ground cinnamon
1 (14 ounce) can sweetened condensed milk
1 (14 ounce) can cream of coconut, shaken very well before opening
1 (14 ounce) can coconut milk, shaken very well before opening
1 (12 fluid ounce) can evaporated milk
1 1/2 cups rum (such as Bacardi®), or to taste
Add cinnamon to a large bottle or other container that can hold at least 8 cups using a funnel. Pour sweetened condensed milk, cream of coconut, coconut milk, evaporated milk, and rum through the funnel. Shake or stir well to combine.
Refrigerate coquito until chilled, at least 1 hour. Shake or stir before serving.