Put the tofu, oil, vinegar, lemon juice and salt into the blender. Open the pour spout in the lid and turn it on low. Pour in the water until it is smooth. Turn off the blender and scrape down the sides as necessary.
Store for up to two weeks in an air-tight container in the refrigerator.
The mayonnaise will firm up after a few hours in the refrigerator.
Spread on sandwiches, use as a dip for french fries, or use as a base for coleslaw, French or Russian salad dressing. Mix with crumbled tofu for Eggless Egg Salad.