1. Heat the oil to 350°F in a deep fryer or in a 4-inch-deep (or deeper) cast-iron skillet over medium heat. The oil should be at least 2 inches deep; add more oil if needed.
2. Meanwhile, make the ravioli: In a small bowl, stir together the ingredients for the filling until well combined.
3. To assemble the ravioli: Lay one slice of prosciutto on a sheet of parchment paper so that the short end is toward you. Lay another slice over the top of the prosciutto so you make a Greek cross with four “arms” to wrap around the filling. Spoon about 1 heaping table-spoon of the filling into the center of the prosciutto cross. Fold one arm of the prosciutto over the filling. Continue folding the arms around the filling to make a square, making sure that the filling is covered well. Using your fingers, press down around the filling to even it out into a square shape. Repeat with the rest of the prosciutto and filling.
4. Working in batches, fry the ravioli in the hot oil for about 2 minutes, or until crisp on the outside. Remove from the oil and serve.

Tip:

1. Once the oil is cool, strain it and store it in mason jars in the fridge for future use. It can be used up to 4 times.
2. The ravioli can be assembled 2 days before frying and stored in the fridge for an easy dinner.

Note:

1. Mascarpone is the traditional choice here, but cream cheese works just as well.