Cut the tofu block into 1/2-inch thick rectangular pieces. Pat dry with a paper towel.
Heat a tablespoon of oil in a large non-stick skillet, carefully add the tofu pieces (tofu breaks easily) and sear over medium to medium high heat until lightly golden brown (about 3 - 4 minutes each side).
Meanwhile, prepare the sauce by mixing all ingredients together. Spoon the sauce over the tofu pieces. Slightly lift a side of the tofu pieces to get the sauce under them. Simmer for 3 - 4 minutes over medium low heat. Flip them over and simmer for another minute or two. Serve warm or cold with a bowl of rice.