I posted a long time ago about how cooking vegetarian and vegan is more green, and suggested a few basic ideas for vegetarian cooking. But vegan cooking, now that is a lot harder.
As mentioned previously, for someone new to non animal cooking it is really easy to make food that tastes like cardboard. Vegans will tell you that they don't miss it, but meat adds a lot of flavor to food, in a lot of ways. Vegetarians get much of it back with butter, cheese, eggs and cream, which vegans eschew. However, by taking a look at what meat brings to the table, one can start thinking of ways to replace the flavor aspect of the meat, and not just the protein and iron.
First, animals are mostly salt water. Meat naturally contains a lot of moisture and a lot of salt, along with several other organic compounds that create the complex flavor. Remember when your 7th grade science teacher told you that your blood is chemically similar to seawater? Well the same is true of cows, chickens, pigs, and all other tasty animals. So, to get that complex saltiness, the best replacement is Sea Salt. Sea salt tastes better because of random inclusions, and if you are cooking meatless do not be shy about sprinkling a little extra in there. Also, if your ingredients are generally dry, adding some moisture can help break down food and bring out flavors. I always use some water, some acid like vinegar or citrus juice, and some alcohol like wine when I cook.
Next item: fat. Most meat contains a lot of fat naturally, to which restaurants almost always add more fat. Fat serves a lot of purposes in cooking, lubrication and moisture retention e.g. It also makes food taste richer and more satisfying. At this point a health conscious person will probably protest, saying "so your answer to tastier food is to add salt and fat?" I know it sounds like a recipe for a heart attack, but think about this: if you have chosen to cook a vegan meal, you have chosen to remove a ton of fat and salt, I am just recommending you add some of it back in. Also, you can use healthier sources of fat like olive or canola oil.
Finally, there is the slightly lesser known concept of umami, which is basically the savoriness of meat. Think of a simple chicken or beef stock, and that is exactly the flavor of umami. It comes from the amino acids in protein rich foods, and it is sorely lacking in many vegan recipes. But don't despair, there are several simple ways that you can get it into your meatless dishes.
The first is mushrooms. I personally feel that the "white" and "brown" mushrooms you get in the grocery store have no flavor at all, a dissatisfying texture, and may not actually be real food. But if you are saving $$ by not buying meat you can splurge a little on fancy mushrooms, and you will be rewarded for your extravagance with excellent flavor. Other umami makers: seaweed (in its many forms), soy sauce, and wonderful miso paste. Miso paste is the basis for miso soup, as you might have guessed, but when used in place of bullion it is excellent as a base for any vegan sauce or soup, especially when flavored with soy sauce and served with delicious fried chanterelle mushrooms... mmmumami.
In short, we evolved to love the flavor of meat, but that doesn't mean that we have to eat it with every meal. And with a little creativity, we can trick our tongues into getting that salty, fatty, umami sensation without a single animal product involved. Since meat and dairy production is way more damaging to the environment than vegetable production, cooking vegan on a regular basis actually makes a big difference. Especially if your vegetables are local. Also, since animal products are more expensive (generally) than vegetable, you can save a ton of money too.