Heat the butter in a pan. Saute the mushrooms and asparagus with a little salt and pepper just until cooked. Scoop out and transfer to a plate.
Add the olive oil to the remaining butter in the pan. Saute the onion, garlic and bell peppers with salt and pepper for about a minute.
Add the rice and paprika, stir well to coat every grain with oil.
Pour in the wine. Stir. Allow to boil, uncovered, until most of the wine has been absorbed by the rice.
Ladle in a cup of simmering meat broth, stirring the rice until the liquid has been absorbed. Add another cup of broth, again, stirring until the rice has absorbed most of it. Season with salt and pepper as you cook, tasting occasionally.
Repeat until the rice is done. The level of doneness is such that when biting a grain, there should be the slightest resistance at the center. In pasta lingo, it's al dente.
Stir in the Parmesan and parsley.
To assemble, ladle the risotto into shallow bowls. Scatter the sautéed mushrooms and asparagus around the mound of rice. Top with a slice of prosciutto di Parma. Garnish with more grated Parmesan and parsley.