Creamy sausage and potato bake combines smoky sausage slices and tender potatoes in a rich cream sauce. This hearty, protein-packed family casserole is simple to assemble and perfect for busy weeknights.
Preheat your oven to 375°F. Generously butter a 9x13-inch baking dish for easy cleanup and to prevent sticking.
Peel and slice the russet potatoes into 1/4-inch thick rounds for even tenderness. Halve the smoked sausage lengthwise, then slice into 1/4-inch half moons. Thinly slice the yellow onion.
In a large skillet over medium heat, melt the butter. Add sliced onions and sauté for 3–4 minutes until translucent. Stir in garlic powder and dried thyme, cooking 1 minute more to bloom the spices.
Layer half the potatoes in the baking dish. Top with half the sautéed onions, sausage slices, and sprinkle with half the salt and pepper. Repeat layers with remaining potatoes, onions, and sausage, finishing with the remaining seasonings.
Pour the heavy cream evenly over the casserole. Cover tightly with foil and bake for 40 minutes. Remove foil, top with shredded cheddar, and bake uncovered for another 15–20 minutes until potatoes are tender and cheese is golden and bubbling.
Let rest 10 minutes before serving to allow the creamy sauce to thicken. Slice and serve hot, ensuring each portion gets sausage, potatoes, and plenty of creamy sauce.