Specialty Coffee for Cold Brewing, Primos Coffee Co (Medium Roast, 12 Oz.) Combine 1 part coarsely ground Primos coffee to 2 parts cold, filtered water. Stir, cover with lid &amp; leave 12-14 hours. Strain coffee using a paper filter, fine mesh strainer or cheesecloth. Mix 1 part concentrate with 1 part water or milk. For cold coffee, cold water, milk and/or ice may be used. For hot coffee, add boiling water. Keep the strained concentrate in the fridge for 7-10 days.