Line an 8- or 9-inch square baking dish with aluminum foil. Place the tomatoes in a small bowl and cover with hot water. Let soak while preparing the teff.

Spray a medium saucepan with olive oil spray and place over medium heat. Sauté the scallions for about 3 minutes, until softened. Add the teff and water. Increase the heat to high and bring to a boil. Cover, reduce heat to low, and cook for 10-15 minutes, stirring occasionally, until the liquid is absorbed and the mixture resembles a thick porridge. Drain and chop the sundried tomatoes. Stir them into the teff mixture along with ¼ teaspoon salt. Pour the cooked teff into the baking dish and spread it into an even layer. Refrigerate for several hours or overnight.