Preheat oven to 350 f. Press mashed potatoes onto bottom and up sides of a greased 9-inch deep -dish pie plate. Brush with 1 tbsp.oil. Bake 30 minutes or until edges are golden brown.

Meanwhile,in a large skillet,heat remaining oil over medium-high heat. Add the mushrooms ;cook and stir for 3-4 minutes or until tender. Add garlic cook 1 minute longer. Remove from heat. Stir in spinach,bacon rosemary;spoon over crust. In a small bowl,whisk eggs,milk and pepper until blended;stir in cheese. Pour over mushroom mixture.

Bake 25-30 minutes longer or until golden brown and a knife inserted near the center comes out clean. Let stand 10 minutes before cutting.