In a stock pot, heat olive oil over medium-low heat. Trim the ends off the scallions and chop through the light green stem. Save the dark green tops for topping. Add the scallions to the pot with the garlic and ginger. Cook, stirring occasionally for 2 to 3 minutes until the garlic and ginger is fragrant. Add in the soy sauce and miso, stirring up any pieces of scallion stuck to the bottom.
Measure in the vegetable broth and water. Bring to a boil, reduce to a simmer, and add in the ramen noodles. Cook for 4 minutes then add in the cabbage. Cook for another 4 to 5 minutes until the ramen and cabbage is tender. Stir in the sesame oil, remove from heat, and divide into 2 bowls. Serve with a sprinkle of sesame seeds, chili flakes (if desired), and scallions.