Heat a large cast iron skillet over medium heat and add a small amount of water. Add your sweet potatoes to the skillet and cover to steam for 5 minutes until tender.
Move sweet potatoes to the side of the skillet and add your tofu to the skillet. Use the back of a wooden spoon to mash. Top with seasonings and begin to scramble, incorporating sweet potatoes. Scramble for 2-3 minutes, adding a little olive oil if desired.
Add in spinach and tomatoes and scramble to heat through until spinach is wilted and tomatoes have softened.