Cut 1/2 an inch from top of the tomatoes and bell peppers to create a lid, being careful to keep stem intact. Set aside.
For the tomatoes: use a sharp paring knife and cut around the inside at the sides. Next cut a "X" into the center, being careful not to cut sides or bottom. Use a spoon and scoop out the tomato pulp and place in a bowl. Repeat with remaining.
For the bell peppers: clean the inside membranes and seeds and discard.
In a food processor puree the tomato pulp, red onion and garlic.
In a large skillet over medium heat add 3 tablespoons of olive oil. After a minute pour in the tomato onion puree. Cook 3 minutes. Add the 2 tablespoons of tomato paste and the cubed eggplant, zucchini, oregano, salt and pepper. Cook for 3 minutes and stir in the rice, chicken stock, pine nuts and golden raisins. Cook for 8 minutes on low. Turn off heat and stir through the fresh mint and parsley. Season to taste.
Divide the filling into each of the prepared vegetables up to the top. Place each cut lid on top of filling. Transfer to a large roasting pan coated with oil or cooking spray.
Preheat oven to 350°F. In a measuring bowl mix together the warm water, oil and tomato paste.
Scatter the cut potatoes around the stuffed vegetables and pour the water, oil, and tomato paste mixture over and around all. Cover with foil and bake for 1 hour. Remove foil and continue to bake another 30 minutes. Potatoes should be fork tender.