What sauce / spices can make a tofu steak taste like a beef steak I had an unbelievably good tofu steak in a restaurant in Tokyo many years ago.  I have never been able to reproduce it.

It tasted uncannily like a beef steak.

What sauce / spices could I use to mimic the steak flavour?
I don't know anything about cooking tofu, so this is purely addressing the beef flavor part. If you want to make something bland taste more like beef, one the largest issues is going to be adding umami flavor. It is present to some degrees in meats, cheeses, mushrooms, soy sauce, and tomatoes. I'd start with a sauce containing several of these items, and then add some complementary flavors (peppers, citrus, sugar, etc).