Heat milk in microwave until scalding, approximately 3 minutes. Whisk eggs; mix in sugar and cinnamon. Slowly whisk in hot milk. Lightly grease 6 custard cups. Place 2 peach slices in bottom of each cup and top with 1 tablespoon of butterscotch topping. Pour custard mixture in cups. Cook in microwave for 15 to 20 minutes. Cool in refrigerator and invert on serving places. Surround with remaining peach slices. Dust with powdered sugar and garnish with mint sprigs.