Build the Flavour Base: Heat the olive oil in a large, heavy-bottomed pot or Dutch oven over a medium-low heat. Add the chopped onions, carrots, and celery. This combination is known as a soffritto and is the foundation of countless wonderful dishes. Cook, stirring occasionally, for 10-12 minutes until the vegetables have softened and the onion is translucent, but not browned.

Add Aromatics: Add the minced garlic, dried thyme, and dried rosemary to the pot. Cook for another minute, stirring constantly, until fragrant. This step toasts the herbs and garlic, deepening their flavour.

Add Root Vegetables: Tip in the diced parsnips and potatoes and give everything a good stir to coat the vegetables in the oil and herbs. Cook for 2-3 minutes.

Introduce Liquids: Pour in the vegetable stock and the tin of chopped tomatoes. Add the bay leaf and season with a generous pinch of salt and a good few grinds of black pepper.

Simmer Gently: Bring the soup to a boil, then immediately reduce the heat to low, cover the pot with a lid, and let it simmer gently for 20 minutes, or until the potatoes and parsnips are tender when pierced with a knife. What works best for me is keeping it at a very gentle bubble, not a rolling boil.

Add Final Touches: Stir in the frozen peas and cook for another 3-5 minutes until they are bright green and tender. Remove the pot from the heat. Fish out the bay leaf (and fresh herb sprigs, if you used them).

Season and Serve: Stir in the optional lemon juice – it really brightens everything up. Taste the soup and adjust the seasoning with more salt and pepper if needed. Ladle into warm bowls, garnish with fresh parsley, and serve immediately.