Cook the soy steaks in very strong vegetable broth for 1/2 hour (I make the broth almost twice as strong as stated on the packaging).
Meanwhile prepare the marinade. To do this, mix the remaining ingredients (onions and garlic, of course, cut) in a measuring cup. Salt is not required, the vegetable stock is sufficiently salted.
When the steaks are ready (they are soft and easy to cut), drain the vegetable stock. Then put approx. 250 ml each of the marinade in a freezer bag and add 3 steaks that are still hot.
I freeze the 4 bags, so I always have steaks when I want to grill spontaneously. Thaw before grilling and then grill like normal steaks.