Mix all ingredients, except the bitters, in a large glass pitcher. Chill for an hour to overnight. Serve with a splash of Angostura bitters in each glass, garnished with a wedge of pineapple.
How to Make Rich Simple Syrup: Combine 1 cup sugar with 1/2 cup water in a medium sauce pan. Bring to simmer over medium heat, stirring to dissolve the sugar. Once clear and slightly thickened, remove from heat and allow to cool. Keep in a mason jar or glass bottle in the fridge for up to 6 months. See this post for more information on simple syrups.