Ingredients
For the steak and potatoes:
- 1 ½ pounds sirloin steak (or ribeye or strip steak), cut into 1 to 1 ½ inch cubes
- 1 ½ pounds baby potatoes (red or yellow), quartered
- 1 tablespoon olive oil
- Salt, to taste
- Black pepper, to taste
- 1 teaspoon paprika
- 1 teaspoon dried thyme or Italian seasoning
For the garlic butter:
- 6 tablespoons unsalted butter, softened
- 4–5 cloves garlic, finely minced
- 1 tablespoon fresh parsley, finely chopped
- ½ teaspoon salt
- ¼ teaspoon black pepper
Optional additions:
- ½ teaspoon crushed red pepper flakes
- 1 tablespoon Worcestershire sauce
- 1 tablespoon lemon juice
- ½ cup sliced onions
- ½ cup sliced mushrooms
Equipment Needed
- Heavy-duty aluminum foil
- Mixing bowls
- Knife and cutting board
- Tongs
- Baking sheet (for oven method)
Step 1: Prepare the Garlic Butter
In a bowl, combine softened butter, minced garlic, chopped parsley, salt, and black pepper. Mix thoroughly until fully combined.
If you want stronger flavor, allow the garlic butter to sit at room temperature for 15–30 minutes before using so the garlic infuses the butter.
For deeper flavor, you can slightly sauté the garlic in butter for 30 seconds before mixing. Let it cool before adding to the raw steak.
Step 2: Prepare the Potatoes
Wash and dry the potatoes thoroughly.
Cut them into even pieces, about 1 inch in size. Uniform size is very important so they cook evenly.
In a large bowl, toss the potatoes with olive oil, salt, pepper, paprika, and thyme. Make sure every piece is coated.
Important tip:
Because potatoes cook slower than steak, cut them smaller than the steak pieces. If your potatoes are large, microwave them for 3–4 minutes first to partially soften them. This guarantees they finish cooking at the same time as the steak.
Step 3: Prepare the Steak
Pat the steak dry with paper towels. This helps achieve better browning and flavor.
Cut into cubes about 1 to 1 ½ inches.
Season generously with salt and black pepper. You may also add Worcestershire sauce or a small drizzle of olive oil for added richness.
Optional flavor boost:
For extra tenderness, let the seasoned steak sit at room temperature for 15–20 minutes before assembling packets.
Step 4: Assemble the Foil Packets
Preheat oven to 425°F (220°C) if using oven method.
If grilling, preheat grill to medium-high heat (about 400–425°F).
Lay out 4 large sheets of heavy-duty foil (about 12 x 12 inches each).
Divide the seasoned potatoes evenly among the foil sheets, placing them in the center.
Top each portion with steak cubes.
Add 1–2 tablespoons of garlic butter on top of each packet.
If using onions or mushrooms, distribute them evenly now.
Fold the foil:
- Bring the long sides together and fold tightly.
- Fold the ends inward to fully seal.
- Leave a little room inside for steam circulation.
- Make sure packets are sealed well to prevent leaking.
Step 5: Cooking Methods
Oven Method
Place packets on a baking sheet.
Bake at 425°F for 20–30 minutes.
For medium steak:
- Check at 20 minutes.
- Potatoes should be fork tender.
- Steak should be cooked to desired doneness.
If you want slightly browned steak edges, carefully open the packets during the last 5 minutes and broil briefly.
Grill Method
Place packets directly on the grill grates.
Close lid and cook 15–25 minutes.
Flip once halfway through cooking.
Campfire Method
Place packets on hot coals (not direct flames).
Cook about 20–30 minutes, turning carefully with tongs halfway through.
Step 6: Check for Doneness
Carefully open one packet (watch for hot steam).
Potatoes should be fork tender.
Steak internal temperatures:
- Rare: 125°F
- Medium rare: 130–135°F
- Medium: 140–145°F
- Medium well: 150°F
If potatoes need more time, reseal and cook an additional 5 minutes.
Step 7: Rest and Serve
Let packets rest unopened for 5 minutes after cooking.
This allows juices to redistribute inside the meat.
Open carefully and garnish with extra parsley, a squeeze of lemon juice, or freshly grated Parmesan if desired.
Serve directly in foil for easy cleanup or transfer to plates.
Texture and Flavor Control Tips
For crispier potatoes:
Open foil during last 5–7 minutes of cooking.
For more sauce:
Add 1–2 tablespoons beef broth before sealing packets.
For richer flavor:
Add a splash of heavy cream to the garlic butter mixture.
For smoky flavor:
Add a pinch of smoked paprika.
Delicious Variations
Cheesy Garlic Butter Version
Add shredded mozzarella or cheddar during the last 5 minutes of cooking.
Spicy Cajun Version
Replace thyme with Cajun seasoning and add red pepper flakes.
Herb Butter Version
Add rosemary and oregano to the butter.
Vegetable Loaded Version
Add zucchini, bell peppers, or asparagus.
Storage Instructions
Refrigerator:
Store leftovers in airtight container for up to 3 days.
Reheating:
Reheat in oven at 350°F for 10–15 minutes or microwave in short intervals.
Freezing:
You can assemble packets and freeze before cooking.
Thaw in refrigerator overnight before cooking.
Make-Ahead Instructions
You can assemble foil packets up to 24 hours in advance and refrigerate.
This makes it perfect for meal prep, camping, or entertaining.
Serving Suggestions
Serve with:
- Fresh green salad
- Garlic bread
- Roasted vegetables
- Steamed broccoli