What do you do to maximize hops flavor in your beers? Is it best to add flavor hops with 30, 20 or 15 minutes left in the boil? Or do you get more flavor from whirlpooling, dry hopping, or some combination of the above? I have seen recipes for flavor hops additions any where from 10 to 30 minutes. What is the "sweet spot" for getting the most (or best) flavor out of your hops?