In a large pot, melt oil and butter and sauté onion and garlic for 3-4 minutes, then add in potatoes and allow to sweat for a couple of minutes.
Next add in frozen peas and cover with stock, season with salt and pepper and allow to simmer on a medium heat for 25-30 minutes until potatoes are tender.
Place prosciutto on a lined baking tray and put in the oven for 12-15 minutes until crispy.
Once the soup is ready, blend into a smooth consistency, pour in cream and season with extra salt and pepper if needed.
If you wanted an extra smooth consistency you could then pass the soup through a sieve.
Garnish with a drizzle of extra cream and crispy prosciutto.