In a large soup pot, heat the oil over medium heat. Add the fennel seeds and the garlic and cook, stirring often, until the garlic is softened but not gold, about 2 minutes. Add the scallions, serrano and lemon zest. Cook, stirring occasionally, until the scallions are soft, about 5-6 minutes.
Add 7 cups of water to the soup pot. Increase the heat and bring to a simmer. Add leeks, fennel, snap peas and asparagus. Season with a generous pinch of sea salt, reduce heat to medium and let simmer until the vegetables are tender, about 5 minutes. Add the spinach and the peas and cook for another minute. Remove from the heat and add the fresh herbs. Season to taste with sea salt and done. Bon appétit!
Keywords: spring, minestrone