Fry the garlic in hot oil, chopped not very finely.
Add pumpkin and fry it for 5-7 minutes.
Mix vinegar, soy sauce, sugar and salt for the marinade. Mix well and pour into the pan with pumpkin. Simmer over high heat until some of the marinade has evaporated and the pumpkin is soft (about 10 minutes). Pepper the stewed pumpkin with ground white pepper (optional)