Deep within the pine-forested hills north of Leadville, Colorado, there’s a tiny restaurant with a peculiar requirement. If you want one of its coveted tables, you’ll have to get there under your own steam. In the summer, diners arrive for their reservations in hiking boots. In the winter, they ascend to the Tennessee Pass Cookhouse via snowshoes or skis. While a snowmobile is available for guests unable to make the walk, diners are encouraged to travel the mile-long approach on foot whenever possible. The car-free perimeter preserves the quiet solitude…