Leek, Potato and Pea Soup - Cooking like a Boss

5 ¹⁄₃ large leeks	sliced	sweat 10 min	boil and simmer 10-15 min	simmer 5 minutes	blend	serve
120g 0.12kg 0.265lb 4.23oz butter
2 ²⁄₃ medium potatoes
2 ²⁄₃l 2666 ²⁄₃ml 178tbsp 533 ¹⁄₃tsp 11.3cup 4.69pint stock
300g 0.3kg 0.661lb 10.6oz frozen peas
2 ²⁄₃tsp 0.013l 13 ¹⁄₃ml 0.889tbsp 0.056cup 0.023pint mint sauce
1 ¹⁄₃tbsp 0.02l 20ml 4tsp 0.085cup 0.035pint parsley
salt
pepper
blob of soured cream