1 1/2 pounds (680 g) ground beef (80β90% lean)
1 medium onion, finely chopped
2 cloves garlic, minced (optional)
1 teaspoon salt, divided (plus more to taste)
1/2 teaspoon black pepper, divided
1 teaspoon dried Italian seasoning or dried parsley
2 pounds (about 900 g) russet or Yukon Gold potatoes, thinly sliced
2 tablespoons butter, for greasing the baking dish
1 1/2 cups shredded cheddar cheese (or a mix of cheddar and mozzarella), divided
1 can (10.5 oz / 295 g) cream of mushroom soup (or cream of chicken)
1 cup milk (whole or 2%)
1/2 teaspoon paprika (optional, for color and flavor)
1/2 teaspoon garlic powder (optional)
1/2 teaspoon onion powder (optional)
Chopped fresh parsley or green onions, for garnish (optional)
Preheat your oven to 375Β°F (190Β°C). Lightly butter a 9x13-inch (23x33 cm) baking dish, making sure to coat the bottom and sides so the potatoes donβt stick.
Prepare the beef mixture: In a large skillet over medium-high heat, cook the ground beef and chopped onion until the beef is browned and the onion is soft, about 7β9 minutes. If using, stir in the minced garlic during the last minute of cooking.
Season the beef: Drain off any excess grease if needed. Stir in about 1/2 teaspoon of the salt, 1/4 teaspoon of the black pepper, and the Italian seasoning or dried parsley. Taste and adjust seasoning if you like. Remove from heat and set aside.
Slice the potatoes: While the beef cooks, wash and peel the potatoes (peeling is optional if youβre using thin-skinned potatoes like Yukon Gold). Slice them into thin rounds, about 1/8-inch thick. The thinner they are, the more tender theyβll be when baked.