Place a wok or large skillet over high heat. Add the vegetable oil and bacon and stir-fry until golden and crisp, about 2 minutes. Sprinkle the sugar over the bacon and toss. Add 1/4 teaspoon soy sauce (watch out-the oil will bubble up) and continue to stir-fry until the bacon is glazed, about 30 seconds. Transfer the bacon to a bowl with a slotted spoon. Add the garlic, ginger and red pepper flakes to the drippings in the pan and stir-fry until fragrant, about 30 seconds. Add the broccoli and cook until crisp, 2 to 3 minutes. Add the rice, the remaining 2 teaspoons soy sauce, the broth and glazed bacon. Toss to heat through.
Push the fried rice to one side of the pan, crack the eggs into the other side and scramble until set, about 1 minute. Mix the eggs into the rice and stir in the watercress. Divide among bowls and serve with mustard or chili sauce, if desired.