Heat 1 tablespoon olive oil in a nonstick skillet over medium heat until shimmering.
Add the thinly sliced scallions and cook, stirring occasionally, until softened, about 3 minutes.
Add the diced tomato and cook until softened and slightly saucy, about 2 minutes.
Pour the beaten eggs over the vegetables, season with salt and black pepper, and stir gently.
Cook, stirring occasionally, until the eggs are set but still soft, about 4–5 minutes, then remove from heat and serve immediately.