Cut tofu “lengthwise” to create 6 equally sized squares. Set aside.
Heat olive oil in a medium to large saute pan over medium high heat. Add onion, and saute, stirring frequently, and cook until they begin to soften, approximately 3 minutes.
Add tofu in a single layer, sprinkle with some salt, and raise the heat to 1 number below high. Cook for just 1 to 1 ½ minutes per side, to just brown the tofu and the onions. Keep your eyes on it to avoid burning! Remove from heat.