- 1 tablespoon extra-virgin olive oil, or as needed
- 10 white mushrooms, minced
- 1 shallot, minced
- 1/2 teaspoon dried thyme
- 1/2 teaspoon garlic powder
- 1/2 teaspoon dried sage
- 1/2 teaspoon ground black pepper 1/4 teaspoon salt
- 1/4 cup chopped fresh parsley
- 2 cups fresh spinach
- 1 teaspoon Dijon mustard
- 1 (2 pound) pork tenderloin, butterflied and pounded flat
- 4 slices prosciutto
- 2 tablespoons extra-virgin olive oil
- Preheat oven to 350 degrees F.
- Heat 1 teaspoon olive oil in a skillet over medium heat; cook and stir mushrooms, shallot, thyme, garlic powder, sage, black pepper, and salt in the hot oil until liquid has evaporated and mushrooms and shallots are softened, 5 to 10 minutes. Add parsley; cook and stir for 1 minute. Mix in spinach; cook and stir until spinach is wilted, about 5 minutes. Stir in mustard. Remove from heat.
- Place pork tenderloin on a work surface; lay prosciutto atop tenderloin. Spread mushroom-spinach mixture over prosciutto, leaving 1/2-inch border on all sides. Tightly roll tenderloin around the filling and tie together with kitchen string to keep closed.
- Heat 2 tablespoons olive oil in a large skillet over medium heat; place rolled tenderloin in the hot oil. Sear until all sides are golden brown, about 10 minutes. Transfer seared tenderloin to a 9×13-inch casserole dish.
- Bake in the preheated oven until pork is no longer pink in the center, 25 to 30 minutes. An instant-read thermometer inserted into the center should read at least 160 degrees F.