Preheat oven to 350 degrees
Add 8 ounces of Italian sausage into a large oven proof non-stick skillet and cook until cooked through and browned
Transfer the browned italian sausage onto a plate and set aside for now
Add the chopped potatoes and diced onions into the same skillet and cook until the potatoes are just tender
While the potatoes are cooking, whisk 8 eggs with 1/4 cup of heavy cream, 1/3 cup of finely chopped fresh herbs and a pinch of salt and black pepper until frothy in a separate bowl
Once the potatoes are just tender, add the browned Italian sausage back into the skillet and spread the potatoes, onions and sausage evenly throughout the skillet
Pour the egg mixture over the skillet and top with 4 ounces of shredded mozzarella
Transfer the skillet into a 350 degree oven and cook for 16-18 minutes or until the eggs are mostly set
Transfer the frittata onto a cutting board and slice into wedges
Serve garnished with sour cream, plain Greek yogurt or hollandaise sauce
Store leftovers in an airtight container in the refrigerator