Prepare the vegetables: Remove the tough core from the fennel. Set aside the fronds for serving. Chop the rest into large pieces. Peel and dice the potato.

Sauté the onion: 3 tablespoons of extra virgin olive oil into a pot. Sauté the finely chopped onion over low heat for 5-6 minutes until softened. Add the crushed garlic and sauté for another minute.

Add the vegetables: Add the fennel and potato to the pot. Sauté together for 3-4 minutes.

Cook: Add 6 cups of water or vegetable broth. Once it comes to a boil, reduce the heat to low. Cook for 20-25 minutes until the vegetables are very tender.

Blend: Add 2 tablespoons of lemon juice. Blend with an immersion blender until smooth or slightly textured. Add salt and black pepper.

Serve: Pour into bowls. Drizzle the remaining 2 tablespoons of olive oil on top. Garnish with fennel fronds and serve hot.

Save the green fennel fronds for serving, not for the soup; they are used for both garnish and aroma. The soup can be served slightly textured, not completely smooth. Do not run the blender for too long.