I still remember the best cup of tea I ever had. It was at a Mediterranean restaurant on the Las Vegas strip. After an excellent meal of falafel, hummus, baba ganouch, pita bread, and lamb, I ordered the tea and was presented with a pot of steaming water and a container of fresh, wet whole tea leaves. You let the tea leaves sit in a basket strainer in the cup to steep until the desired strength. It was delicious, but very strong, because I wasn't used to brewing it like this. Tea has caffeine just like coffee does, but at a slightly lower concentration. I was wired for the rest of the day. But it was delicious, completely unlike making your tea with a little bag of dried particles.
Lots of restaurants think that tea is the simplest thing to prepare: just heat water, throw in a tea bag, and Bob's your uncle. But some helpful tips will turn the least-considered beverage in your restaurant into an experience that will deeply impress the customer, since most restaurants don't bother to make their tea better at all.
First, start with cold water, which you don't let boil for too long. The reason why we start with cold water is that it has more oxygen in it, and as you boil the water, the oxygen is slowly driven out. The more oxygen the water has, the better the tea will taste. Have you ever drank a glass of water that has been sitting out for a day or so, and noticed that it tasted kind of flat? That's because all of the oxygen that is naturally dissolved in the water has leached out into the open air. Seriously, try two cups prepared side by side and you will taste the difference.
Use a tea cozy, and if you are serving tea for just one guest, just fill the water pot up only part way. Making single-cup tea tends to make the tea bitter - and will cost the same as a whole pot. The tea cozy is to keep the tea hot for a longer time. This is helpful if your guest will like their tea strong or will be enjoying it over a leisurely period of time. If you are steeping the tea, make sure to remove the tea bag when the tea is at your desired strength or it will end up getting bitter and nasty.
Next, while your are boiling with the kettle, pre-heat the tea pot. Simply get a shot of the hot water when it starts to boil from the kettle and swish it around in the pot, but be careful not to give yourself a scald! If your tap is hot enough, you can also fill the pot and let it sit while you are boiling the kettle. Now, why do we do this? Because of physics. A cold pot will absorb more heat from the boiling water poured into it than a warm pot, and we want our water to be hot and good to steep all of the essence of the tea. Remember your thermodynamics!
A bit of tea trivia: In England, they steep the tea in the pot itself instead of the individual cup. And then they don't wash the pot from one use to another! Rather like a tobacco smoker's pipe, they consider the buildup of residue inside the pot to impart a flavor to each successive cup. An anecdote floating around out there has it that the maid washing the family tea pot is considered a firing offense! Don't know how this applies to your set-up, but you'll probably be washing the tea pot anyway.
Not many people know that tea has grades. The terms used in the grading and classification of tea, while less obtuse than those used for wine, are still intricate and detailed. The most basic division is by the color of the tea leaf, which depends on the level of fermentation.
Green tea is not fermented at all, and has a very fresh, almost grassy aroma. Oolong tea is only partially fermented and has a light brown color. Black tea is of the type most commonly served in the West, and is fully fermented. The leaves are completely black, and the flavor is robust and almost like coffee.
Further classification of black tea goes by the shape and size of the tea leaf. This is mostly based on which parts of the leaf are included and the methods of processing the leaves. There are four basic classifications of leaf size, which are then subdivided in more specific categories according to, at last, what kind of tea bush the leaf came from.
Whew! And all this time, you thought it was so simple! Just a bag and water. Well, that bag which comes in a box of fifty that you buy a brick at a time contains what is called "dust": the lowest possible grade. Dust is ranked below "fannings" (little pieces of broken leaves), which is below "broken leaf", and that of course below "whole leaf". Of course, Oolong and black teas will have to be dried out, but with green tea you can have the fresh leaves straight off the bush, if that's how you insist.