Sauté the aromatics: Heat 2 tbsp olive oil in a pot over medium heat. Add finely chopped onion and sauté until translucent.
Add garlic: Stir in minced garlic and cook for 1 minute until fragrant.
Cook the vegetables: Add sliced carrots and chopped celery. Sauté for 3–4 minutes until slightly tender.
Add potatoes: Stir in diced potatoes, season with salt and pepper, and cook for another 2 minutes.
Add water: Pour in 6 cups of water (or vegetable broth) and bring to a boil. Reduce heat and simmer for 10 minutes.
Cook the noodles: Add 1 cup of noodles and cook for 5 minutes, or until tender.
Add spinach: Stir in 1 cup chopped spinach and cook for another 5 minutes.
Finish the soup: Remove from heat, add chopped parsley and 1 tbsp lemon juice. Stir well and serve hot.