Heat the oven to 400°F/200C. Line a baking dish with parchment paper. Roughly chop eggplant, peppers and tomatoes. Pour vegetables into prepared baking dish, season with salt and drizzle evenly with olive oil. Roast vegetables for about 20-30 minutes until tender.
Meanwhile, heat the olive oil in a shallow pan. Add onions and garlic. Cook, stirring until onions are soft and translucent.
Add the ground beef and cook until fully brown. Transfer in a colander. Drain. Return the meat to the saucepan. Pour the diced tomatoes together with juice into a saucepan. Turn heat to low.
Add roasted vegetables and parsley, stir well. Season to taste with salt, pepper and sugar. Put a lid on and leave to cook for another 5 minutes.
Remove from the heat and cool thoroughly. Spread moussaka on dehydrator trays covered with non-stick sheets or parchment paper. Dehydrate at 63C/145F for 8-10 hours until brittle.
Divide moussaka in portions and pack in separate zip lock bags.
To rehydrate 1 portion=1 cup dried moussaka: Pour dry moussaka mixture into the pot; add 1 cup water and stir well.
Place pot over medium heat and bring to a boil. Cook, stirring occasionally, for about 5 minutes.
Remove from the heat, cover, and let stand another 5-10 minutes to rehydrate meal completely.
