1. Preheat oven to 375 degrees Fahrenheit. After you squeeze moisture out of the tofu, cut it into slices width wise, about 1/2" wide. Cut each slice into 3 pieces (nuggets). Set aside.
2. In a medium bowl, mix flax, soymilk, soy sauce, oil, and vinegar. In a larger bowl, mix all dry ingredients. Lightly spray a large baking sheet with oil.
3. Using 1 hand for dry, and 1 for wet, dip each nugget in the wet ingredients, then lightly coat with the dry mix. You can shake these around in a container or bag, but I like to do them individually.
4. Now, redip each in wet, and thoroughly coat with the remaining dry ingredients. Remember to add more panko or onion flakes to the mix, if needed. Use the "wet hand" to dip into the wet mix, place in dry, and use dry hand to press dry mix onto nugget. You can also sprinkle the mix on the nugget, and press it in.
5. Place all coated nuggets on the pan. They should be completely coated in the dry mixture. Bake for 10 minutes. Turn over nuggets after 10 minutes, and bake for another 10. The coating should be golden brown, with some darker pieces. If needed, bake another 4 to 5 minutes on each side.
I like to dip these in the sweet dijon mustard sauce from this recipe: http://vegweb.com/index.php?topic=27394.0 [1].
Source of recipe: This recipe was inspired by the seitan nugget recipe on VeganDad (blog).