From the New York Times
Recipe: Cold-Brewed Iced Coffee
Published: June 27, 2007
Time: 5 minutes, plus 12 hours’ resting
1/3 cup ground coffee (medium-coarse grind is best)
1. In a jar, stir together coffee and 1 1/2 cups water. Cover and let rest at room temperature overnight or 12 hours.
2. Strain twice through a coffee filter, a fine-mesh sieve or a sieve lined with cheesecloth. In a tall glass filled with ice, mix equal parts coffee concentrate and water, or to taste. If desired, add milk.
Yield: Two drinks.
NOTE: To make hot coffee, dilute concentrate one-to-one with water and heat in the microwave.
This stuff is a godsend for those summer-morning commutes. I usually mix the concentrate and water in a pitcher and keep the result in the fridge, ready to be poured into my travel mug. If you take sugar, you might find that you don't need as much in cold-brewed coffee.
HANDY HINT: I put my grounds in extra-large tea bags (available at many Asian groceries), which means I only need to strain once and makes clean-up easier.