In a medium pan over medium-high heat, brown and crisp up the prosciutto. This will take about 5 minutes. 

Once the prosciutto is browned and starting to crisp up, remove it to a paper towel-lined plate while you finish the gravy. Check to see how much grease is in the pan. If it's less than 2 tablespoons, you should supplement it with butter until you have about 2 tablespoons of grease in the pan.

Add the flour, stirring it into the grease. This stirring process will help your gravy to stay smooth and lump-free. 

Cook the flour for 1 to 2 minutes, stirring often.

Add 1/4 cup of red wine to the flour/grease and stir to incorporate into the flour paste. Then add 1 cup of chicken or beef stock. Reserve the rest of the stock to use if the gravy is too thick. Taste the gravy to see if you need to add salt or want to add black pepper. I usually end up adding a small pinch of both. 

Cook the gravy for around 5 minutes. This time is variable because your liquid amount is variable, and you may want a thinner or thicker gravy.  If the gravy is too thick, add more stock, a quarter cup at a time, until you get to a thick, smooth, pourable consistency. When you get to the consistency that you desire, remove the pan from the heat and serve.

Sprinkle the crispy prosciutto pieces on top of whatever you've doused with gravy to add extra texture and flavor.