01 - Heat olive oil in a large pot over medium heat. Add the diced onion and sauté for 3 to 4 minutes until translucent and softened.
02 - Stir in the minced garlic and grated ginger. Cook for 1 minute, stirring constantly, until fragrant.
03 - Add the sliced carrots to the pot and cook for 2 to 3 minutes, stirring occasionally, allowing them to pick up slight color.
04 - Pour in the vegetable broth and water. Bring to a boil, then reduce heat to low and simmer for 15 to 20 minutes until the carrots are fork-tender.
05 - Remove the pot from heat. Use an immersion blender directly in the pot, or carefully transfer the soup to a countertop blender in batches, and blend until completely smooth and silky.
06 - Return the soup to the pot if needed. Whisk in the miso paste and soy sauce until fully dissolved. Gently warm over low heat but do not boil, as high heat diminishes miso's flavor and beneficial properties.
07 - Taste the soup and adjust seasoning with salt and freshly ground black pepper as needed.
08 - Ladle into warm bowls and garnish with chopped scallions, toasted sesame seeds, and a light drizzle of sesame oil if desired.