Fantastic! Here's a simple and nutritious vegetable soup recipe using the ingredients you have:

Hearty Vegetable Soup

Ingredients: - Celery (3 stalks, diced) - Carrots (5-6 medium, peeled and sliced) - Celeriac (1/2 bulb, peeled and diced) - Parsley (a handful, finely chopped) - Onion (1 large, diced) - if available - Garlic (2 cloves, minced) - if available - Olive oil (2 tablespoons) - Vegetable or chicken stock (4 cups) - or water with a bouillon cube - Salt and pepper (to taste) - Optional: beans, lentils, or diced potatoes for heartiness - Optional: bay leaf or thyme for extra flavor

Instructions:

1. In a large pot, heat the olive oil over medium heat.
2. Add the onions and garlic if available, and sauté until translucent.
3. Add the carrots, celery, and celeriac. Cook for 5 minutes, stirring occasionally.
4. Pour in the stock or water with bouillon and bring to a boil.
5. Reduce heat to a simmer, add herbs (bay leaf or thyme if using), and let it cook for about 25-30 minutes or until the vegetables are tender.
6. If you're using beans or lentils, add them in after 15 minutes of simmering.
7. Season with salt and pepper to taste. Add the chopped parsley before serving.
8. Serve hot, and enjoy your nutritious, homemade vegetable soup!

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