Combine cornstarch with water to form a smooth slurry.

In a small bowl, mix chicken stock, Chinese rice wine, and sugar.

In another bowl, combine soy sauce, chili bean paste, garlic, and ginger.

Heat peanut oil in a wok over high heat.

Stir-fry ground pork for 2 minutes, or until browned.

Add soy sauce mixture to the pork and bring to a boil.

Add tofu and stock mixture to the wok.

Simmer for 1 minute, or until the sauce has thickened.

Transfer the Ma Po Tofu to serving bowls.

Sprinkle with green onions.

Serve hot with steamed rice.