Slice the tomatoes and mushrooms, and then chop the onions. Set dehydrator temperature at 135°F (57°C) and dehydrate for 6 hours.
Combine 3 tablespoons of the dehydrated mushroom, 3 tablespoons of dehydrated tomatoes, and 3 tablespoons of onion to a Ziploc bag. Add the remaining ingredients into the bag - the instant rice should make about 3 cups of cooked rice.
Just add about 5 cups of boiled water to a bowl.
Add in all the ingredients packed into the Ziploc bag and stir. Leave for about 15 minutes in a cozy until well-rehydrated.
The meal is ready when the rice and veggies are soft. Enjoy.