I’d suggest trying to cook them in something with plenty of spices. Soy is pretty flavorless on its own, but it usually takes on the flavor of whatever you’re cooking it in pretty well. I personally associate the flavors of fennel seed and sage with sausage, at least the kind of Italian sausage usually sold in the US, so you could try those in, for example, a pasta sauce, but otherwise I’d just suggest trying it in your favorite highly-spiced dish.