1 teaspoon minced fresh thyme or 1/4 teaspoon dried thyme
Flatten chicken to 1/4-in. thickness; place one cheese and prosciutto slice down the center of each. Roll up jelly-roll style, starting with a short side; secure with toothpicks.
In a small skillet, brown chicken in butter and oil on all sides; transfer to an 8-in. square baking dish coated with cooking spray. Cover and bake at 350° for 20-25 minutes or until a thermometer reads 170°.
In the same skillet, saute onion and garlic until tender. Stir in flour until blended; gradually add wine. Bring to a boil; cook and stir for 2 minutes or until thickened. Stir in the remaining ingredients. Discard toothpicks from chicken rolls; serve with sauce.