Coffee Brewing Basics
When we brew coffee, we dissolve the soluble solids from ground coffee in water. There are a few variables at play in how complete this solvation is:
Coffee particle size — Whether your coffee is pulverized for Turkish brewing or coarsely ground for your French press will affect not only the strength, but also the flavor, caffeine content, and body of your coffee. There is unfortunately no one-size-fits-all grinding option. Always fit your grind to the type of brewer you'll be using.
Water to Coffee Ratio — Too much water and your coffee is weak; too little, and, as our delivery driver Al says, it'll put some hair on your chest. The optimum extraction is 20%, meaning that 20% by weight of the coffee grounds you started with have been dissolved. The SCAA standard brew ratio is 1.65 grams of coffee per ounce of water. "Oh, that's super easy, no problem, I can figure that out right now," you say? I know. We make coffee in kitchens, not laboratories, and kitchen implements measure in volume, not weight. I use one and a half tablespoons of medium-fine ground coffee per 10-ounce cup when I use my pour over. Try that and see if it works for you. If not, tweak it till it does.
Contact Time — As a general rule, the time that hot water is in contact with coffee grounds is proportional to the size of the ground particles. Finer grind, shorter brew time--like espresso. Coarser grind, longer brew time--like French press. A great way to get acrid, bitter, over-extracted coffee is to steep coffee ground for espresso in a French press.
Water Temperature — Grandpappy* used to say, "Coffee that's boiled is coffee that's spoiled." The ideal brew temperature is 195-205 degrees Fahrenheit. Because water boils at 202 or so degrees here in Albuquerque, water straight out of your kettle should be fine.
OTHER IMPORTANT STUFF TO CONSIDER:
Buy good coffee from a local roaster (might I suggest Red Rock Roasters?)
Grind your coffee just before you brew
Use freshly drawn water that isn't softened (softened water causes over-extraction)
*My grandfather was a dentist who drank Nescafe, and this is not something he actually ever said.