Preheat oven to 350°F
Crack each egg and place it into a mixing bowl.
Add salt, pepper, hot sauce and heavy cream to eggs.
Whip with a wire whisk until smooth and combined well.
Place butter into a cast iron pan over medium low heat. Melt butter and let it heat until it just starts to brown.
Add onion and sweet pepper into the butter and cook until soft and slightly translucent.
Add sausage into the pan with the onion and peppers and heat through.
When the vegetables and sausages are done, add the egg mixture into the same pan.
Stir the eggs slowly into the onions, peppers and sausage allowing them to cook slightly. Scrape the bottom of the pan often to keep them from sticking to the bottom.
Once eggs are cooked half way, add in the grated cheese. Stir well to combine.
Place cast iron with the egg mixture into the oven and bake for an additional 15-20 minutes until the frittata is cooked all the way through and knife placed into the center comes out clean.
Garnish with more shredded cheese or fresh parsley if desired.