This Slow Cooker Vegetable Soup is a warming, wholesome bowl packed with tender leeks, carrots, onions and pearl onions in a rich, savoury broth. Simple to prepare and left to simmer all day, it’s the ultimate nourishing comfort food.
Ingredients
- 2 large leeks, sliced
- 3 carrots, peeled and chopped
- 1 large onion, chopped
- 8–10 baby pearl onions, peeled
- 2 celery sticks, sliced
- 2 garlic cloves, minced
- 1 tbsp tomato purée
- 1.2 litres (5 cups) vegetable or beef stock
- 1 tbsp Worcestershire sauce (optional)
- 1 tsp dried mixed herbs
- 1 bay leaf
- Salt and black pepper, to taste
- 1 tbsp olive oil
- 1 tbsp plain flour (optional, for thickening)
Slow Cooker Vegetable Soup: Instructions
- Add the olive oil to the base of the slow cooker.
- Place the leeks, carrots, onion, pearl onions, celery, and garlic into the pot.
- Stir in the tomato purée until the vegetables are lightly coated.
- Pour in the stock and Worcestershire sauce.
- Add the dried mixed herbs, bay leaf, salt, and pepper.
- Stir everything together well.
- Cover and cook on low for 7–8 hours, or on high for 4–5 hours, until the vegetables are tender.
- If a thicker soup is preferred, mix the flour with a little cold water to form a paste and stir it in during the last 30 minutes.
- Remove the bay leaf before serving.
- Taste and adjust the seasoning as needed.
- Ladle into bowls and serve hot, with crusty bread on the side.
This rustic vegetable soup is naturally low in fat, budget-friendly, and perfect for meal prepping or freezing in batches for busy weeknights.


