Wash and drain the spinach. Peel and chop garlic, onion and ginger.
Heat oil in a wok or frying pan. Sauté the onion, garlic and ginger in it. Add the spinach and let it collapse while stirring for 2-3 minutes. Add soy sauce, sugar and 100 ml water, continue cooking for 1-2 minutes.
Season to taste with salt. Sprinkle with grilled onions.