These are a couple tips I've learned that I thought I'd pass on:

- Chef Ming Tsai uses a combination of lemon juice and salt as a substitute for soy sauce for his son who has food allergies.

- A standard vegan substitute for Parmesan cheese is:
1 cup Brazil nuts
1 teaspoon chopped garlic
1/3 teaspoon salt
Process the three ingredients in a food processor till fluffy.

So what are some substitutes that you've learned?