Heat the broth in a saucepan.
In a medium saucepan, over high heat, mix the olive oil with half of the butter and add the finely chopped onion. When transparent, add the saffron and sauté for a few more minutes. Add the rice and sauté, without browning.
Add the white wine and stir until it evaporates. Lower the heat a little.
Start adding the broth in several batches and let it reduce until you can see the bottom of the pot in each batch. Add more broth, and repeat the process at least 3 times, boil for 15-18 min in total. Season with salt and pepper.
When the rice is ready, reduce the heat to the minimum and add the Mascarpone Quescrem and stir.
Once the dish is ready, add the Parmesan and Iberian ham slices just before serving.