In medium bowl, mix together pork, soy sauce, cornstarch and sherry. Marinate in refrigerator at least 30 minutes.
In small bowl, stir together broth, oyster sauce and cornstarch. Set aside.
In wok or heavy skillet, heat 1 Tbsp (15 mL) canola oil over medium-high heat. Add half of garlic and half of ginger and sauté until fragrant, about 30 seconds. Add pork and stir-fry about 4 minutes, browning meat and cooking until no longer pink. Scoop pork onto a separate plate. Set aside.
In wok or skillet, heat remaining 1 Tbsp (15 mL) canola oil over medium-high heat. Tip wok to coat bottom of pan with canola oil. Add remaining garlic and ginger. Stir-fry until fragrant, about 30 seconds. Add broccoli and sauté for 1 minute. Pour in broth and cover wok or skillet. Cook for 3 minutes.
Remove cover and cook until most of liquid is evaporated. Add pork. Stir sauce, making sure cornstarch is dissolved, then add to pork and broccoli. Cook until sauce is thickened, about 2 minutes. Stir occasionally to coat meat and broccoli with sauce. Sprinkle in green onions and cook for another minute.