Chinese Broccoli Beef Soup

Bahan-bahan (6 porsi)

• 1 & 1/2 pounds flank (or skirt steak)
• 2 tablespoons cornstarch
• 1/2 teaspoon black pepper (fresh, more to taste)
• 1/4 cup soy sauce (reduced sodium or regular)
• 1 medium yellow onion (very thinly sliced (about 1 and 1/2 cups))
• 6 cloves garlic (minced)
• 1 tablespoon ginger (minced)
• 2 -3 tablespoons olive oil (divided (for browning the meat))
• 1/2 teaspoon kosher salt
• 8 cups beef broth (*)
• 2 large heads broccoli (cut into florets)
• 1/4 cup oyster sauce
• 1 -4 tablespoons Sambal Oelek chili paste (**)