Ingredients
Equipment
Method
Roast the potatoes
- Preheat oven to 425F. Toss baby potatoes with olive oil, salt, and black pepper in an oven-safe cast iron skillet.
- Roast at 425F for 30-35 minutes until golden and crispy, turning once if needed for even browning.
Cook the French onion topping
- Meanwhile, cook yellow onions in butter over medium-low heat for 25 minutes until deep golden and jammy, stirring occasionally to prevent scorching.
- Stir fresh thyme leaves, beef broth, and Worcestershire sauce into the onions, then simmer until the liquid is absorbed and the onions look glossy.
Bake and serve
- Spoon the jammy onions over the roasted potatoes, spreading to cover most surfaces.
- Bake at 425F for 8-10 minutes until the Gruyere is melted and bubbly, with lightly browned spots.
Notes
For maximum crisp edges, keep the skillet hot as you roast and avoid crowding the potatoes. Store leftovers in the fridge up to 3 days; rewarm in a 400F oven until hot and edges re-crisp. Freezing is not recommended because the onions soften when thawed. For a lower-fat option, use reduced-fat Gruyere and swap half the butter for olive oil.
