Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Reliable recipes to replace questionable conversions of the past

Here at last is a guide to successful baking at high altitudes which will delight cooks who reside between 3,000 and 10,000 feet above sea level and have found their breads flat and their cakes collapsed. Baking at high altitude is challenging, yet only a handful of small-press cookery titles and regional offerings have addressed the special challenges of baking at high altitude, until now. Purdy has stayed at five different locations and elevations across the country to adjust recipes to perfection: Pie In The Sky presents reliable recipes to replace questionable conversions of the past.