Prepare the potatoes: Peel the Red Bliss potatoes and grate them using a coarse grater. Place the grated potatoes in a clean kitchen towel and squeeze out excess moisture. This step is key for achieving crispy potatoes.

Season the potatoes: In a large bowl, combine the grated potatoes with salt, pepper, and fresh thyme. Mix well to evenly distribute the seasonings.

Prepare the cheese filling: In a separate bowl, mix together the requeijão, shredded mozzarella, and shredded provolone until well combined.

Assemble the rösti: Divide the grated potatoes into portions for each rösti (about 1 cup per rösti, depending on desired size). Heat 1 tablespoon of olive oil and a small amount of butter in a non-stick skillet over medium heat. Spread half of each portion of grated potatoes in the skillet, pressing it down to create an even layer. Place a spoonful of the cheese mixture in the center, then cover with the remaining portion of potatoes, pressing gently to encase the cheese.

Cook the rösti Cook each rösti for about 5-7 minutes on one side until golden brown and crispy, then carefully flip and cook for another 5-7 minutes on the other side. Repeat for each rösti, adding more olive oil and butter as needed.

Serve: Once each rösti is golden and crispy, transfer to a serving plate. Serve hot to enjoy the melted cheese center!