Start by talking to harris the chef, in the camp close to the Dragonspine entrance, and you will be asked to find him some chilled meat.
Getting Chilled Meat
Chilled meat can only be obtained in Dragonspine, and you get them by killing boars that are frozen in ice.
You can find some snow boars in several locations spread through out the map, but the easy one to get to, and the one we need to go is in the marked location shown above. There about 3 frozen boars there, and another one down the slope. Melt and kill all 3 boars there and you will be greeted by a surprise fight by the true ruler of Dragonspine? In order to finish the quest, you will need to defeat the snowboar king and get its items.
The snowboar king has a lot of HP, and can deal some good damage if you get hit with his charge. You can make it slam into the wall by standing close to a wall, and dodge it as he charges. This will stun him for a few seconds, allowing you to get some quick hits. His charge is much easier to dodge if you are not in melee range when he's starting to charge. He also has a jumping attack that will continuously drop ice. Circle around the area to avoid falling snows. His last attack is when it summons multiple snow boars to throw ice at you, impairing your vision for a few seconds.
If you need to find a heat source, go down the slope, through the one exit out of the snowboar arena fight, then activate the ruin brazier close to the frozen boar. If you get defeated, you can simply return to the location and fight it again. The boss will also spawn again the next day, in case you want to farm more chilled meats, or to enjoy the fight.
Once you defeat the snowboar king, head back to chef Harris and hand in the required items. He will give you the recipe for Goulash and you'll need to make 1 for him to finish the quest. After the conversation ends, you can talk to him again at 6 PM (in-game time) to get a free Goulash
Goulash is a very useful food for traveling in Dragonspine. It helps reduce sheer cold's build up rate, potentially saving you the trouble and stress of finding any heat source every minute or so.
You can get Carrots and Tomatoes from outside of Dragonspine, but Chilled Meat is from Dragonspine only. Tomatoes can be bought from General Goods NPC in Mondstadt, next to the Timaeus with the crafting table. Carrots can be found in the wild, or from expeditions.