Preheat oven to 425°. Place four 6-ounce ramekins or custard cups upside-down on a large baking sheet. Grease outsides of ramekins well. Cut puff pastry into quarters; shape each quarter around a ramekin Bake 14-16 minutes or until golden brown., Meanwhile, in a large skillet, melt 1 tablespoon butter over medium-high heat. Add mushrooms; cook and stir 2-3 minutes or until lightly browned. Stir in spinach until wilted; remove from pan., In same pan, heat remaining butter over medium heat. Pour in eggs; cook and stir until eggs are thickened and no liquid egg remains. Gently stir in goat cheese, chili sauce and mushroom mixture., Carefully remove pastries from ramekins and place right-side up on individual serving plates. Line bottoms and sides of pastries with prosciutto. Fill with egg mixture; sprinkle with tarragon.