Wash the vegetables in the river near Cookie's tent by heading to the river just west of the tent ( -22, -123, 567 ) /waypoint -22, -123, 567 and use the Cookie's Vegetables in your inventory.
Roast the vegetables by clicking the smaller firepit just outside Cookies tent. ( -65, -116, 665 ) /waypoint -65, -116, 665 (Only ONE person can be roasting the vegetables at a time, while they are the fire is unclickable.)
Wait a minute until you can click the fire pit again.
Put the vegetables in a bowl on the table right next to Cookie.