Mince garlic. Dice onion, celery, carrot, bell pepper, leek and zucchini.
In a large nonstick saucepan or soup pot, heat up olive oil over medium heat. Add onion, celery, carrot and garlic and sauté for about 5 minutes.
Add bell pepper, leek and zucchini and sauté for another 10 minutes.
Stir in tomato paste and sauté for 2 minutes.
Add Italian herbs and vegetable stock or water. Stir to combine. Cover and let simmer over low heat for 20 minutes.
Let cool slightly then transfer everything to a blender and blend until smooth. Alternatively, you may use an immersion blender.
Season to taste with salt and pepper. Serve immediately with pasta or use it to dress protein of choice.
Let cool completely before storing in airtight containers in the fridge or freezer.