Cooking with alcohol mystifies a lot of people, so I thought I'd weigh in on the subject. I'm a huge fan of mixing liquor into my food as often as possible, because there are many enzymes in food that can only be activated by it. First, I'd like to dispel a myth. All of the alcohol does NOT cook away. The most you'll be able to cook off is somewhere in the area of 15%, reasonably, unless it's a really long and really slow cook. So, before we embark on this, that's a warning. It won't be enough to get you drunk, but it is there. So, on to the tips.
1: Flavor combos. Whiskey always goes with steak. Burbon and tequilla always go with chicken. rum always goes with pork. Vodka and the tomato love one another. You can mix and match, obviously, according to the recipe, but these are tried and true rules.
2: A little dab will do you. One of the BIGGEST mistakes people make when cooking with alcohol is overdoing it. Alcohol in a dish is a flavor accent. A shot of liquor in with your meat is more than plenty. With sauces, unless you're making a LOT, a half a shot should be more than adequate. You want the alcohol to break up those enzymes and add a bit of flavor, not overwhelm the dish. We're not making jello shots.
3: DO NOT FLASH. Think about this for a second. When you add alcohol, you're adding it to flavor your food, right? When you flash fry, all of the flavor is evaporated directly off of the pan. Not much gets into the food. To truly work a dish with alcohol, you want to keep the heat under the flash point of the liquor. You have to use less, and you get better flavor. Remember the golden rule: flash for style, simmer for flavor.
4: Beware the alcohol marinade. Beer is a great marinade. As is wine. Liquor can make a very biting taste on food if you let it sit for too long. Liquor has a strong flavor, and when you get every single fiber of the meat fully imbued with it, the results can be pretty wicked. If you want an alcohol marinade using liquor, my suggestion is keep it short, and don't add too much. Chicken with a bit of tequilla, some lime juice, and a bit of garlic is an amazing marinade. Add too much more on top of that and you're going to nuke the flavor of your chicken and make it taste like a liquor bomb. You're always better off (Barring specific circumstances) poking holes in the meat and letting it marinade for an hour, rather than overnight. There's no need to make the meat taste like an AA meeting.
5: Don't be afraid to experiment. A dab (key word. Dab.) of alcohol makes a lot of foods more interesting. If you're curious about how a certain liquor would taste in a certain dish, add a tiny splash. You'll catch the undertone, and be able to tell if adding enough to make a difference would be a good idea.
6: You don't have to cook with what you'd drink. That's bs. Liquor tastes different when cooked. Port wine is GROSS, but port sauces can have an amazingly subtle, rounded flavor. The trick is cooking with the proper amount. Unless the liquor is taking center stage, don't be afraid to skimp. If it's just a hint of liquor? I tend to use cheap tequilla to cook, and serve it with a jose cuervo margarita. It's still the same liqour, and drinking the good stuff will very well accent the stuff you put in the dish. The same holds true with wine, in many cases. Beer? Beer is something else. Always use a good beer.
Obviously there are exceptions to all of this. That's just a general guideline on how to become proficient with liquor in everyday cooking.
So, with that out of the way, another question (see? told you I was question happy today). What's your favorite dish that has alcohol in it? I love vodka sauce, but my downright favorite has to be my bourbon sausage gravy. Served over some egg noodles? Yum.