Deglazing can be done with any liquid. Alcohol or stock is most frequently used, but water works just as well. The method of choice to achieve the best flavor is alcohol followed by some type of stock. While wine is most commonly used (red wine with red meat and white meat with white wine), but options include brandy, cognac, Marsala, sherry, port, or even vodka. The type of alcohol chosen is determined by the nature of the dish and the flavor profile desired. For example, for a sweeter sauce you would use a port. For a more complex, earthy and aromatic sauce, you might try a good cognac. And, in the case of fajitas, tequila works best.
Before deglazing, drain any excess fat from the pan being careful not to dislodge and toss any of the browned bits. If you are adding aromatics (shallots, onions, garlic), simply sauté them with some salt and pepper in the leftover pan drippings. Depending on how little drippings you have, you may even need to add some oil and/or butter to the pan. Once the aromatics are sautéed you’re ready to deglaze.
Carefully add alcohol since it can self-ignite, especially brandies and hard liquors creating a flambé effect. The traditional warning is to remove the pan from the stove when adding the alcohol but spontaneous combustion is still possible. If your goal is to flambé the alcohol and it did not self-ignite, tip the pan so it touches the flame or use a match. Once the alcohol is added, or once the flames have subsided if you’re flambéing, bring it to a boil as you scrape the fond off the bottom of the pan. A straight edged wooden spatula is the most effective tool for this job. You are now deglazing. All of those intensely flavored little bits will invitingly melt into the sauce, creating a complex web of flavor. Usually the alcohol is reduced to at least half and sometimes even further. Vaporizing it down to a syrupy glaze is a key flavor enhancing technique.
Once the alcohol is reduced add the stock. Continue to boil and scrape, reducing the stock to at least half. If you are not using alcohol simply add the stock from the get-go and deglaze accordingly. Once the stock is added, season with salt, pepper, herbs, zest, etc. Or, if not using stock, (such as when making a sauce based solely on wine), add the seasoning after the initial deglazing with the alcohol. Once the alcohol and/or stock has been reduced to the desired thickness, the final step is to add cream or butter. Add cream and simmer for a few minutes to concentrate it or if using butter, add a tablespoon or two of cold butter and remove the sauce from the heat the instant it has melted. Strain the sauce and serve.
The same procedure is used for making a sauce for roasts. If making a gravy, after you add flour to the drippings and cook it to make a roux, deglazing occurs when the stock is added. Whisk the stock into the roux scraping up the fond as you go.
Sautéed vegetables can be deglazed by adding vegetable or chicken stock. For tomato sauce, deglaze the garlic and/or other sautéed aromatics with wine, reduce, and then add the tomatoes. For rice pilaf and risotto, deglaze the aromatics and rice with wine before adding the stock. Deglazing the fond will also boost the flavor of soups and stews. Virtually anything that can be seared or sautéed can be deglazed.