Peel and chop the onion. Fry the frozen peas and onion in 1 tbsp. hot oil in a saucepan. Salt and pepper. Add 1/4 l water and broth, bring to the boil. Simmer covered for about 10 minutes.
Puree the soup, let it cool down and cover and keep it cold.
Wash mint and rosemary, shake dry. Put 1-2 stems of the mint aside. Remove leaves or needles from other herbs. Heat 2 tablespoons of oil in a frying pan. Fry the rosemary and bread together.
Season yoghurt with salt and 1 pinch of sugar. Stir buttermilk and mint into the soup, puree. Season to taste. Serve in ice-cold glasses. Garnish with yoghurt and the rest of the mint. Add bread.