5 Minute Winter Soup: A Delicious, Warm, and Healthy!

You can make this winter soup in 5 minutes! It has full of veggies: Leek, carrot and potato along with lentils. With the creamy yogurt egg sauce it is hearty and delicious!
Ingredients:
2-3 leek
2 potatoes
2 carrots
1/2 to 1 cup red lentils
2 tbsp butter
2 tbsp olive oil
1 heaped tbsp flour
meat or vegetable stock or water
salt, black pepper, dried mint
For the sauce:
1 egg
3 tbsp yogurt
3-4 tbsp hot water to temper the mixture
For the pepper oil
2 tbsp butter
1-2 tsp pepper flakes