01 - Heat olive oil in a large pot over medium heat. Add the diced onion and sauté for 3 to 4 minutes until translucent.
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 lightly caramelize.
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 to purée the soup directly in the pot, or carefully transfer in batches to a countertop blender and blend until completely smooth.
06 - Return the soup to low heat. Whisk in the miso paste and soy sauce until fully dissolved. Warm gently without boiling to preserve the miso's live cultures and delicate flavor.
07 - Taste the soup and adjust seasoning with salt and freshly ground black pepper as needed.
08 - Ladle into bowls and garnish with chopped scallions, toasted sesame seeds, and a light drizzle of sesame oil if desired.