Question: legend of zelda breath of the wild how to get warm doublet?
Answer: Read the Old Man's diary in his hut on the Great Plateau, then cook a meal using a spicy pepper, meat and a Hyrule bass. ... 
If you climb to the top of Mount Hylia on the Great Plateau (before you complete the trials on the Great Plateau), the Old Man will appear and give you the warm doublet as a reward.