Heat olive oil in a large pot over medium heat.
Add diced onion and sauté until translucent, about 5 minutes.
Stir in minced garlic and cook for another minute.
Add chopped carrots to the pot and stir well.
Pour in vegetable broth, bringing the mixture to a boil.
Reduce heat and let simmer until carrots are tender, about 20 minutes.
Remove from heat and let cool slightly.
Blend the soup using an immersion blender until smooth.
Return to heat and stir in heavy cream; season with salt and pepper.
Serve warm, garnished with fresh herbs and croutons.