Heat the oil in a large deep skillet over med-high heat. Add the meat and saute until crisp and frizzled, about 1 minute. Remove and reserve.
Reduce heat to medium, add onion and saute till tender(do not brown) about 3 minutes. Add garlic and cook a few seconds, until aromatic. Stir in pumpkin, broth, nutmeg, salt, and pepper and bring to a boil. Transfer to slow cooker, cover and cook 3-4 hours on high, 6-8 hours on low.
Stir in the cream and cheese and heat through, about 5 minute Stir in parsley and garnish with prosciutto.