Pile sliced onions and these 4 ingredients over beef for a baked supper I keep craving week after week

Preheat your oven to 400°F (200°C). Line a large baking sheet with foil for easy cleanup. Tear off 4 large sheets of heavy-duty aluminum foil (about 12×18 inches each). Lightly spray the center of each with nonstick cooking spray if you’d like extra insurance against sticking.

Prep the vegetables: Thinly slice the onions and halve the baby potatoes (or cut larger potatoes into 1-inch chunks). Pat the beef dry with paper towels and slice into strips if it isn’t already thinly sliced.

In a large bowl, toss the potatoes and sliced onions with the olive oil, steak seasoning, and a pinch of salt and pepper if needed. This helps the seasoning coat everything evenly so you’re not trying to sprinkle it into each packet.

Assemble the packets: Divide the seasoned onion-and-potato mixture evenly among the four foil sheets, piling it in the center of each. Top each pile with an equal portion of the sliced beef, spreading it out a bit so it cooks evenly.

Seal the packets: Bring the long sides of the foil up and together over the filling and fold them down tightly to seal, then roll up the short ends to form a snug packet. Leave a little room inside for air to circulate so the steam can help cook everything through.

Place the packets on the prepared baking sheet and bake at 400°F (200°C) for 30–35 minutes, or until the potatoes are tender when pierced with a fork and the beef is cooked through. If your beef is very thin and you prefer it less done, you can open the packets for the last 5 minutes to let some steam escape and reduce cooking time slightly.

Carefully open one packet (watch out for hot steam) and check a potato for doneness. If needed, reseal and bake for an additional 5–10 minutes. When everything is tender, remove from the oven and let the packets rest for 3–5 minutes before serving.

Serve the foil packets directly on plates (kids especially love opening their own) or slide the contents into shallow bowls. Spoon any juices over the top—they’re full of oniony, beefy flavor.

To keep this recipe weeknight-friendly but still flexible, you can easily swap ingredients based on what you have. For a veggie boost, add sliced bell peppers, carrots, or green beans into the packets along with the onions and potatoes (just keep the total amount of veggies about the same so everything cooks evenly). If you prefer a richer flavor, replace some or all of the olive oil with melted butter. For a different seasoning profile, try a packet with taco seasoning and serve with salsa and shredded cheese, or use Italian seasoning and finish with a sprinkle of Parmesan after baking. You can also trade the potatoes for sweet potatoes, keeping the pieces small so they cook through in the same amount of time. For meal prep, you can assemble the foil packets the night before, store them on a baking sheet in the fridge, and pop them straight into the oven when you get home—just add a few extra minutes of baking time if they’re going in cold. And if you’re cooking for two, simply halve the recipe and make two larger packets instead of four smaller ones.