Spread the potatoes out in an even layer in the bottom of a 9x13" baking dish., then spread the sausage and bacon evenly out overtop.
8 oz bacon, 7 cups thinly sliced russet potatoes, 1 lb ground Italian sausage
Return the bacon grease to the same large skillet you cooked the sausage and bacon in set over medium heat.
Add the onions and garlic, stirring to combine, and saute for 2-3 minutes, just until softened. Add the kale, stirring just until wilted.
1 small white onion, 2 tbsp garlic paste, 6 packed cups washed and chopped kale leaves
Sprinkle the flour out over the skillet, stirring to coat everything, and cook for 60 seconds.
1/2 cup flour
Add the broth to the skillet and whisk it in, then simmer until slightly thickened. Stir in the cream until evenly incorporated.
4 cups chicken broth, 1 - 1 1/2 cups heavy whipping cream
Transfer a a tablespoon of the hot liquid to a small bowl, then add the beaten egg and stir to combine. Stir in another tablespoon of the hot liquid, then one more. Pour the egg mixture back into the skillet, whisking to combine.
1 large egg
Add half the Parmesan cheese sauce to the skillet, stirring, just until melted and smooth. Pour the sauce mixture evenly out over the potatoes.
1 1/2 cups shredded Parmesan cheese
Cover the dish tightly with aluminum foil and bake at 400° for 50-60 minutes. Remove the foil and sprinkle the remaining cheese evenly out overtop. Bake for another 25-30 minutes.
Carefully remove the hot dish from the oven and let it rest for 10 minutes so that sauce sets. Serve & enjoy!