Put the orange juice in a small bowl. Squeeze the grated ginger over the bow to extract the juices, then discard the pulp. Add the tamari, mirin, and maple syrup, ground coriander, and garlic. Mix together and set aside.
Cut the tempeh (or tofu) into thin-ish, bite-sized pieces, and if working with tofu, pat dry with a paper towel.
Put the olive oil in a large frying pan over medium-high heat. When the oil is hot but not smoking, add the tempeh and fry for 5 minutes, or until golden underneath. Turn and cook the other side for another 5 minutes, or until golden. Pour the orange juice mixture into the pan and simmer for 10 minutes, or until the sauce has reduced to a lovely thick glaze. Turn the tempeh once more during this time and spoon the sauce over the tofu from time to time.
Serve the tofu drizzled with any remainin sauce and a squeeze of lime, with the coriander scattered on top.