Sauté the Aromatics: Heat the olive oil in a large stockpot or Dutch oven over a medium heat. Once shimmering, add the chopped onion and sauté for 5-7 minutes, until it becomes soft and translucent. Be careful not to let it brown.

Add Garlic and Rosemary: Add the whole, peeled garlic cloves and the sprig of rosemary to the pot. Stir continuously for about 1-2 minutes until the garlic is fragrant. This step toasts the garlic slightly, which starts to develop its sweet flavour.

Introduce the Chickpeas and Stock: Pour in the drained and rinsed chickpeas and the vegetable stock. Give everything a good stir to combine.

Simmer to Infuse: Bring the mixture to a gentle boil, then reduce the heat to low, cover the pot, and let it simmer for 15 minutes. This is the most important step; it allows the garlic to become completely soft and infuse the entire soup with its flavour.

Prepare for Blending: After 15 minutes, turn off the heat and remove the woody rosemary stem. You can use a fork to pull off any tender leaves and return them to the soup.

Blend Until Smooth: Using an immersion (stick) blender, carefully blend the soup directly in the pot until it is completely smooth and creamy. If you don't have an immersion blender, you can transfer the soup in batches to a standard blender, but be sure to let it cool slightly first and leave the lid's vent open to allow steam to escape. I find that blending for a good 2-3 minutes is what gives it that incredibly velvety texture.

Final Seasoning: Stir in the fresh lemon juice, sea salt, and black pepper. Taste the soup and adjust the seasoning if necessary. The lemon juice really brightens up all the flavours.

Serve and Garnish: Ladle the hot soup into bowls. Garnish with a drizzle of good extra virgin olive oil, a sprinkle of fresh parsley, and a pinch of red pepper flakes if you like a little warmth.