Place coffee, mint and water in measuring cup or Mason jar, stir to mix, cover, and let stand at room temperature overnight.
Strain through a coffee filter set in a sieve into a small pitcher and add brown sugar. Stir until dissolved. Fill 2 glasses with ice and pour coffee over. Stir in half and half to taste. Serve garnished with additional mint.
For a low-calorie variation, substitute nonfat skim milk for half and half.
It’s optional to let the coffee, mint and water stand at room temperature to let the flavors infuse overnight.