Prepare all vegetables by washing and slicing them accordingly.
Heat olive oil in a wok or large frying pan over medium-high heat.
Add onions to the hot oil and sauté for 2-3 minutes until they start to become translucent.
Stir in garlic and ginger, cooking for an additional 30 seconds until fragrant.
Add the sliced bell pepper and carrots, and stir-fry for about 3 minutes until they begin to soften.
Add the sliced cabbage to the mixture, stirring well to combine all the ingredients.
Pour in the soy sauce and sesame oil, tossing the vegetables to coat them evenly.
Continue to stir-fry for an additional 5-7 minutes, or until the cabbage is tender but still crisp.
Season with salt and pepper to taste.
Remove from heat and sprinkle with sesame seeds before serving.