Ingredients
Equipment
Method
Roast the potatoes
- Preheat the oven to 425°F, then toss the potatoes with olive oil, salt, and black pepper in an oven-safe cast iron skillet.
- Roast the potatoes for 30-35 minutes, until golden and crispy.
Make the jammy onions
- Meanwhile, cook the onions in butter over medium-low heat for 25 minutes, stirring occasionally until deep golden and jammy.
- Stir in the fresh thyme leaves, beef broth, and Worcestershire sauce, then simmer until the liquid is absorbed.
Assemble and bake
- Spoon the jammy onions over the roasted potatoes.
- Top with the shredded Gruyere, then bake for 8-10 minutes at 425°F until the cheese is melted and bubbly.
Notes
For the best texture, let the roasted potatoes finish at the oven rack position closest to the heat so the edges stay crisp when you add the onions and cheese. Store leftovers covered in the fridge for up to 3 days; reheat in a 375°F oven until warmed through and the cheese softens. Freezing is not recommended because the potatoes can become mealy after thawing. For a lighter option, replace half the Gruyere with a reduced-fat melting cheese to cut calories while keeping the bubbly melt.
