Baked beef liver and onions is a simple, high-protein dinner made with beef liver and sweet sautéed onions, finished in the oven until just cooked through.
Place the liver in a shallow dish and cover with milk. Let sit for 20–30 minutes. Drain and pat dry with paper towels.
While the liver soaks, hard-boil the eggs. Peel and set aside.
Heat 1 tablespoon butter with the olive oil in a large skillet over medium heat. Add the onions with a pinch of salt, pepper, and sugar. Cook for 10–15 minutes until soft and lightly browned. Set aside.
Preheat the oven to 375°F. Lightly coat a baking dish or sheet pan with olive oil, or line with parchment paper.
Season the liver with salt and pepper.
Arrange the liver in a single layer. Top with the cooked onions and dot with the remaining butter.
Bake for 15–20 minutes, just until cooked through.
Serve hot with sliced eggs and a sprinkle of fresh parsley.
Notes
Storage and Reheating: Store leftover beef liver and onions in an airtight container in the refrigerator for up to 3 days. Keep the onions with the liver so it stays moist.To reheat, warm gently in a skillet over medium-low heat with a little butter or oil. This prevents it from drying out.If you plan to freeze it, wrap tightly and freeze for up to 2 months. The texture may change slightly once thawed. For best results, sauté fresh onions, then add the thawed, sliced liver to the skillet at the end just to heat through.