Root Vegetable and Red Lentil Soup (in a Soup Maker)

This root vegetable and red lentil soup is thick, smooth and full of flavour. It’s made with a bag of prepared casserole vegetables, dried red lentils, paprika and mixed herbs, making it a really easy and inexpensive soup maker recipe.

I served mine with a toasted cheese sandwich for dipping, which turned it into a lovely, filling lunch.

What You Need

For exact quantities, see the recipe card at the bottom of the post.

Casserole Vegetables

I used a 600g bag of Tesco prepared casserole vegetables, which contains a mixture of carrots, swede, potatoes, leeks and onions.

These bags are really convenient for making soup, especially when you don’t have much time for preparation. The vegetables are already washed and chopped, so you can tip them straight into your soup maker.

I did cut a few of the larger pieces of new potato in half to make sure they cooked through properly.

You don’t have to use the Tesco version; any similar mixture of prepared root vegetables will work. Alternatively, you could chop your own vegetables.

Split Red Lentils

Dried split red lentils are perfect for adding to soup maker recipes. They’re inexpensive, a good source of plant-based protein and fibre, and help make the soup naturally thick and creamy.

There’s no need to soak them beforehand, but give them a good rinse under cold water.

Paprika and Mixed Herbs

I kept the seasoning simple with regular paprika and dried mixed herbs.

The paprika adds a gentle warmth without making the soup spicy, while the mixed herbs complement the root vegetables.

You could also use smoked paprika if you prefer a slightly smoky flavour.

Vegetable Stock

I used 1 litre of vegetable stock, which worked well with the vegetables and lentils.

You can make this with a stock cube or pot, or use ready-made vegetable stock. Always make sure the total contents stay within your soup maker’s maximum fill line.

I used Marigold Swiss Vegetable Bouillon Powder, using four level teaspoons to make 1 litre of stock.

Making Root Vegetable and Red Lentil Soup

This is a really straightforward recipe with very little preparation.

Start by checking the vegetables and cutting any larger pieces of potato into smaller chunks.

Rinse the red lentils, then add them to the soup maker along with the prepared vegetables, paprika and mixed herbs.

Pour in the vegetable stock and select the smooth soup programme.

Once finished, check that the vegetables and lentils are completely cooked and soft. Taste and add salt and black pepper as required.

The result is a lovely thick, smooth soup, with a naturally creamy texture from the potatoes and lentils.

How Much Does It Cost to Make?

One of the best things about this recipe is how inexpensive it is.

Estimated Cost of Root Vegetable and Red Lentil Soup

Ingredient	Estimated Cost
600g Tesco casserole vegetables	£1.50
150g dried red split lentils	£0.39
20g Marigold vegetable bouillon	£0.33
1 tsp paprika	£0.04
1 tsp dried mixed herbs	£0.03
Total recipe cost	£2.29
Cost per serving (4 × 350ml)	£0.57

Prices based on Tesco ingredients, October 2026. Costs are approximate and may vary depending on where you shop.

This soup costs approximately 57p per serving, making it an inexpensive option for lunch, particularly when served with some toast or a toasted cheese sandwich.

Is Root Vegetable and Red Lentil Soup Healthy?

This soup contains a mixture of vegetables and red lentils, providing fibre and plant-based protein.

The lentils also help make the soup more substantial without needing cream or other dairy products.

Estimated Nutrition Per Serving

Based on four 350ml portions:

• Calories: 199 kcal
• Protein: 11g
• Fibre: 5g

These figures are estimates and will vary depending on the vegetables, lentils and stock used.

What to Serve With It

I served this soup with a toasted cheese sandwich, which was perfect for dipping into the thick, smooth soup and made it into a really satisfying lunch.

If you make a cheese toastie using two slices of wholemeal bread and 30g mature cheddar cheese, the estimated nutrition for the complete meal would be:

• Calories: 512 kcal
• Protein: 27g
• Fibre: 11g to 12g

These figures are approximate and don’t include any butter or oil used to make the toastie.

You could also serve this soup with crusty bread, buttered toast or a simple bread roll.

The soup itself is satisfying thanks to the lentils and potatoes, but adding bread or a sandwich makes it an even more filling meal.

Storing and Freezing

This is a great soup for making ahead, especially if you want to prepare a few lunches in advance.

In the fridge: Allow the soup to cool promptly, transfer it to an airtight container and refrigerate within two hours. Store at 5°C or below and use within 48 hours.

In the freezer: Once cooled, divide the soup into individual freezer-safe containers. Freeze and use within three months for the best quality.

To reheat: Defrost frozen soup in the fridge, then reheat until steaming hot throughout. Stir well if reheating in the microwave, and only reheat once.

You may find that the soup thickens slightly after being stored, as the lentils continue to absorb some of the liquid. Simply add a splash of water or stock when reheating if needed.

More Lentil Soup Maker Recipes

If you like adding lentils to your soups, check out these for ideas;

• Curried Lentil Soup (In A Soup Maker)
• Carrot and Lentil Soup (in a Soup Maker)
• Bacon and Lentil Soup (in a Soup Maker)
• Tomato and Lentil Soup (in a Soup Maker)
• Butter Bean and Lentil Soup (in a Soup Maker)
• Vegetable and Lentil Soup (in a Soup Maker)
• Curried Chicken and Lentil Soup (in a Soup Maker)
• Sweet Potato and Lentil Soup (in a Soup Maker)
• Potato, Lentil and Coconut Soup (in a Soup Maker)
• Red Lentil and Harissa Soup (In A Soup Maker)