Step 1

In a quart jar, stir the water, coffee, brown sugar, and cinnamon. Cover and refrigerate overnight.

Step 2

Pour the coffee base through a fine-mesh sieve or strainer into a medium bowl, then strain back into the jar for easy storage.

Step 3

For each drink: Fill a tall glass halfway with ice. Pour in the coffee until the glass is about three-quarters full. Add the creamer or milk to taste.

Step 4

Die of happiness.