Add rice and stir. Reduce heat, cover and simmer for 20 minutes.
Meanwhile, heat oil in a small skillet over medium heat.
Saute onions until tender. Set aside.
In a large bowl combine cooked rice, lentils, mushrooms, Worcestershire sauce, salt, pepper, egg, garlic powder, Italian seasoning, parsley and cooked onions; mix well. Press mixture into prepared pan; spread ketchup on top of loaf.