Heat oil and butter in a large wok over medium-high heat.
Add ginger and garlic and sauté for 4-5 seconds.
Add zucchini and onions and saute for a minute.
Now add soy sauce, salt, and pepper powder, and mix well.
Cook uncovered for 6-8 minutes until the liquid released by zucchini is evaporated and they are slightly charred, stirring frequently.
Garnish with chopped scallion greens and toasted white seeds and serve hot.