Heat 2 tablespoons olive oil in a large pot. Stir in onions; cook and stir until the onion has softened and turned translucent, about 5 minutes. Add carrots and parsnips. Cover and cook until vegetables have softened slightly, about 5 minutes.
Stir in the pumpkin puree and stock. Bring to a simmer and reduce heat to low. Cover and let simmer until vegetables are tender, about 40 minutes. Add lemon juice, salt, pepper, and cilantro. Taste and adjust seasonings, if necessary. Remove from heat and allow to cool.
Ladle soup in batches into a food processor and blend until smooth (or use an immersion blender). If soup is too thick, thin with additional stock. Return pureed soup to the pot and heat through.
To make the garnish, heat olive oil in a small skillet. Cook garlic and parsley over low heat 1 to 2 minutes. Stir in paprika. Swirl a half teaspoon of garnish on each serving of soup.