Grate parmesan. Mix ricotta, parmesan, eggs and egg yolks. Season with pepper. Grease 12 wells of a muffin tin. Line each with 2 slices of Parma ham. Fill evenly with ricotta mixture.
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 30-40 minutes. Remove the muffins from the oven and let them cool slightly on a cake rack. Serve lukewarm garnished with basil.