Peel and coarsely chop carrots, onion and garlic.

Add all to pan with oil and fry for 3-4 mins.

Add stock/water and increase heat to boil.

Rinse lentils then add to pan.

Add spices now if including them.

Boil for 10 mins then simmer for 20-30 mins until lentils and carrots are soft and cooked, stirring often.

Add butter if you're using it.

Depending on how thick you like soup, you may need to add more hot water/stock.

Blend until smooth, (season with salt and pepper if required) and serve.