Rustic Sausage and Caramelized Onion Potato Bake

Quick Recipe Version (TL;DR) Yield: 6 servings Prep Time: 25 minutes Cook Time: 1 hour 5 minutes Total Time: 1 hour 30 minutes Quick Ingredients 3 large yellow onions, thinly sliced 1 lb (450 g) uncooked sausage (Italian or country), casings removed 1.5 lb (680 g) Yukon Gold potatoes, thinly sliced 3 tbsp unsalted butter…