Nope! All meals are cooked by chefs and ready to eat, just add boiling water!
Note from Team T4:
We recommend using freshly boiled water.
The meal will rehydrate with warm water, you’ll just need to stir more frequently and wait longer for the food to rehydrate.
Using cold water means you don't get the hot meal ~*experience*~, but it can be necessary depending on your activity (looking at you ocean rowers) so plan to wait at least 45 minutes, stirring occasionally, before you dig in.
Another note from the Team:
Our directions are set for sea level. Rehydration times will be longer at higher elevations.