Heat oil until it starts to shimmer.
Toss in the cumin seeds and cook for about 30 seconds.
Add the onions and a pinch of salt, saute until translucent.
Add the garlic and half the ginger. Saute until the onions start to caramelize and turn golden brown.
Add the carrots, sweet potato and salt to taste.
Add 4 cups of water, bay leaf and turmeric. Turn the heat high and bring to a boil.
Turn the heat down to medium, cover pot and let simmer for 20 to 25 minutes. Until the carrots and sweet potato are soft.
Add in the remaining ginger.
Blend the soup into a puree either with an immersion blender or by transferring the soup into a blender in batches.
Add a little more water, if needed, to get a consistency you like.
Pour the soup back into the pot, bring to a boil.
Add the dumplings and cook for 3 to 4 minutes. Turn off the heat.
Gently stir in the lemon juice.
Garnish with cilantro sprigs.