"This pepper is exploding with spice. Cook with it to create dishes that will raise your body temperature and help you withstand the cold."
The Spicy Pepper is a natural material found in Breath of the Wild. This item can be eaten to recover ½ of a heart, and can be sold to shop-vendors all over Hyrule for 3 Rupees each. Spicy Peppers can be used in many Recipes, and they have a cooking effect of cold resistance, allowing Link to traverse into colder climates. If cooked on an open flame by itself, Link will receive Spicy Sautéed Peppers. If a Pepper is dropped near a flame, it will burn him, becoming a Charred Pepper.
While on the Great Plateau, Link will find Spicy Peppers in several locations, strategically located in areas before Link enters colder climates. There are an abundance of Spicy Peppers located west of the Temple of Time, near an archway before Link enters the color climate. There are a few just north of this archway, near a Bokoblin camp. There are also a number of peppers northwest of the River of the Dead, near a Bokoblin Camp, just before Link crosses the broken bridge into the colder climate. There are also a few on the table in the Woodcutter's House, right next to The Old Man's Diary.
Outside of the Great Plateau, Spicy Peppers are found abundantly in the Wasteland region, throughout the Gerudo Desert. They are also found around the circular road in Tabantha that surrounds Rito Village. There is over two dozen of them in an area of Ridgeland, just southeast of Satori Mountain. They are found more spaced out in the Lake, Faron, Woodland, Hateno, and Dueling Peaks regions.
Hyrule Compendium entry of the Spicy Pepper.