Step 1

In a very large skillet, preferably cast iron, heat the oil. Add the prosciutto and garlic and cook over medium heat, stirring, until the garlic is golden, about 4 minutes. Transfer to a plate.

Step 2

Season the pork medallions with salt and pepper, add them to the skillet, and cook over medium-high heat until well browned on the outside and medium rare, 3 to 4 minutes per side. Transfer the medallions to a plate, and cover to keep warm.

Step 3

Add the balsamic vinegar to the skillet and cook until nearly evaporated, scraping up any browned bits from the bottom of the skillet.

Step 4

Add the arugula and toss until wilted, about 2 minutes. Add the tomatoes and cook over high heat for 3 minutes, stirring occasionally. Stir in the prosciutto and garlic, and season with salt and pepper.

Step 5

Transfer the tomato mixture to a platter, top with the pork, and serve.