Melt the butter in a pan, add the chopped shallot and sauté for a few minutes.
Add the rice and toast it for a few minutes, pour in a little white wine and continue cooking for 15 minutes, adding ladles of hot broth and stirring occasionally.
Meanwhile, in a non-stick pan sauté the prosciutto cut into strips and the grapes cut in half.
A few minutes before the rice has finished cooking, add the prosciutto and grapes, stirring gently.