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.
Beef and onion foil packet dinner served in a shallow bowl
Beef and onion foil packet dinner served in a shallow bowl
Variations & Tips
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.
Foil packets prepped ahead on a refrigerator-ready baking sheet
Foil packets prepped ahead on a refrigerator-ready baking sheet
