Start by cooking your whole potatoes (skin on) in salted boiling water until they’re just tender, not falling apart. This pre‑cooking makes shredding easy the next day and helps the rösti crisp up beautifully.
Once cooled and chilled, peel and roughly grate the potatoes. Toss them with salt, black pepper, and fresh thyme so every bite carries flavor. Serving the potatoes cold helps them bind and crisp later.
In a separate bowl, combine the requeijão (or cream cheese), mozzarella, and shredded provolone. Stir until smooth and creamy — this is the melty heart of your rosti!
Heat the butter and a bit of olive oil in your skillet over medium heat. Add half the shredded potatoes, flattening and shaping them into a pancake that covers the pan evenly.
Spoon the cheese mixture over the potato base, leaving a small border clear so the top layer can seal the cheese in. This creates that gooey center you’re craving!
Spread the rest of the grated potato over the cheese. Press gently so it adheres and covers all the cheese, forming a complete sandwich.
Let the bottom cook until golden, about 5 minutes. Then carefully flip using a plate larger than your skillet, add more butter and oil, and brown the other side too.
Once crispy and golden all over, let the rosti sit off the heat for about 5 minutes. This helps the cheese set a bit so it doesn’t ooze everywhere when sliced.