Thickeners:

Roux

This is a thickener using equal amounts of flour and fat. It is the most common thickener used for soups sauces and gravies. To make it you melt the margarine or heat up oil and then add the flour and cook it over low heat for at least 5-10 minutes to cook out the gluten flavor out of the flour. You then slowly add in the liquid stirring constantly. Then you cook it down until you get the consistency you are looking for. You can make a large batch of roux and then refrigerate or freeze until needed. If you are watching your fat intake you can take some flour and slowly toast it as well. There are several different kinds of roux and you use them according to what you are trying to cook and accomplish color and flavor wise. A pale, or blonde roux should be straw-colored, a brown or black roux will be deep in color, have a nutty aroma, and is used in brown sauces and Cajun cooking.
You can see more about roux here.

Starch thickeners

To avoid lumps, mix the starch with an equal amount of cold liquid until it forms a paste, and then whisk it into the liquid you're trying to thicken. Once the thickener is added, cook it briefly to remove the starchy flavor. Don't overcook! Liquids thickened with some starches will thin again if cooked too long or at too high a temperature.

Cornstarch

I have found that the best way to use cornstarch is to take some starch, add cold water to it and thoroughly mix it with the starch until all the lumps are gone. Right before you add the liquid mixture mix it again to get the starch mixed back in that settled to the bottom.

Arrowroot

Choose arrowroot if you're thickening an acidic liquid. Cornstarch loses potency when mixed with acids.

Tapioca starch

Use tapioca starch for pie fillings. It holds up during long cooking and freezing. It will also give your fillings a glossy color.

Potato starch/flour

This is gluten free as well. I have also used potato flour in making chocolate cakes. Potato flower makes a nice rich dense moist cake.

Any starchy veggies or grains can thicken up a soup or stew.


Potatoes are a favorite of mine.



Gelatin thickeners

Agar-agar


This comes from seaweed and is vegan. Agar is flavorless and becomes gelatinous when it's dissolved in water, heated, and then cooled.
Each of these amounts will firm two cups of liquid: 3 tablespoons agar flakes = 2 teaspoons agar powder = 1 kanten bar To use agar, just soak it in the liquid for about 15 minutes, bring it to a gentle boil, and then simmer while stirring until it's completely dissolved. The liquid will gel as it cools. An acid weakens agar's gelling power, so if you're firming an acidic liquid, use more.

Carrageen

This is seaweed as well.
To use the dried seaweed as a thickener, first rinse it carefully, and then soak it in water until it swells. Next add the carrageen to the liquid you wish to set, boil the liquid for about 10 minutes, then strain out and discard the carrageen.

You can find more thickening tips here.

Flavor in layers

Food is art, and in order to make a great painting, you have to apply the paint in layers. The same is when you are adding herbs and spices to your food. Adding flavor to your dish at different times of the cooking process will create a rich and developed dish.

Taste as you go

This goes hand and hand with flavoring in layers. It is good to taste your food as you are cooking it so you know what it is going to taste like. Remember to try to under salt your dishes until the very end after your sauce has reduced.


Basting

If you are baking a veggie loaf or one of those fake turkeys, to help keep it moist baste it with its juices or water or a simple vegan au jus through the cooking process. This will also add flavor to the dish.


Brazing and deglazing

When you cook tofu, fake meat, veggies or whatever, adding a bit of brownness to the food will add a good flavor to it. Also if the pan has brownness to it from where you were cooking, add a bit of liquid to the pan and scrape the brownness off the pan. This will add a good rich flavor and color to your sauce and make clean up easier.


Uniformity

When you cut up your veggies or tofu make them uniform so they cook at the same speed. This will keep you from having mushy and undercooked food mixed with your perfectly cooked veggies.

Using infused oils

Take some old wine bottles, stuff them with fresh herbs and spices, and then fill them with extra virgin olive oil. Let that mixture sit for at least 48 hours before you use the oil. My favorite is to take about 1/2 cup of rose petals and let that infuse with the olive oil. This is good on roasted potatoes. I think it adds a bit of Middle Eastern flavor. Yum!


Marinate

Build flavor into your veggies and tofu before you cook them by creating a marinade and soaking them for a few hours or overnight. I will use a bit of oil, fresh herbs, garlic, soy, or whatever my mind takes me. I love doing this with tofu to help add flavor to this gift from the gods.

Reduction

A great way to intensify flavor is through reduction. If your sauce is too thin or a bit flat tasting bring it to a light boil and reduce it until you get the consistency or until your flavors get a chance to develop in your dish.

To keep things from sticking

Seasoning the pan by heating it up then adding the oil then making the oil hot before adding your ingredients will help prevent your food from sticking to the pan.


Keep your knives sharp and clean.

To keep your knives really sharp, you'll need to care for them on a regular basis. The techniques of sharpening and steeling your knife are quite simple. A sharpening stone has two sides: one rough, one fine. The stone needs, first, to be soaked in either water or mineral oil (never substitute one for the other). You will have either a waterstone or an oilstone. Place the stone on a damp cloth to stabilize it. Then, holding your knife at a 20-degree angle to the stone, draw the entire length of the knife blade over the stone. Use your free hand to exert pressure on the blade firmly and evenly from tip to hilt. Turn the blade over and repeat the process, over and over at a 20-degree angle, until the blade is very sharp. Always allow an equal number of passes for each side. After wiping the sharpened knife clean of any metal and oil, use the steel to finish the edge. Holding the steel with your fingers safely behind the guard, repeatedly slide the knife from hilt to tip down one side, then the other, over the steel. The knife will "sing" when this is done properly and quickly. Steeling alone does not sharpen a knife, but hones it. It actually realigns the molecules on the sharpened edge, straightening the edge. Between sharpenings with the stone, use the steel frequently to keep the blade in good condition. Never use your knife on a metal or marble surface. It is always good to use a vinyl or wood cutting board.

Don't be afraid to experiment.

Some of the most basic and the best food and sauces came from experimentation and by accident. Do not be afraid to mix different things together. Be creative and use cooking as an artistic outlet. Even the best cooks out there create unappetizing food.

Hopefully the above tips and techniques will help you become a better cook. Food is more than just keeping alive. Food does not have to be bland mush. I have started a couple of threads in the forums if you have techniques you would like to share and if you have any questions you would like to ask.

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