Heat the olive oil in a large saucepan set over medium heat. Add the celery, leek, bell pepper and carrot, and saute so they all begin to soften, about 5 to 6 minutes. Allow the vegetables to sweat but not turn brown – you just want them to soften.
Add the garlic, dried oregano, rosemary, oregano and thyme, and continue to cook, stirring everything together for another minute.
Pour in the broth and add the bay leaf, lemon zest, Parmesan rind, chickpeas and beans. Stir to combine and season to taste.
Cover the pot with a lid, bring to a low simmer and cook for 30 minutes.
Once done, remove the cheese rind and the lemon zest. If you prefer a creamier soup (which I do!), use an immersion blender to blend some of the soup. Alternatively, let the soup cool slightly, then ladle 2 cups of the soup into a blender or food processor, blend to a smooth consistency, then add that back into the soup. **Be sure to let the soup cool a bit and hold the lid on your blender so you don’t burn yourself or end up with soup on your ceiling.**
Remove the soup from the heat and add the arugula. The residual heat will soften the leaves.
Garnish with the strips of Parmesan.