Preheat the oven to 375 degrees and lightly spray a 9 inch loaf pan with oil, or line the bottom with parchment paper to prevent sticking.
Saute the onion, carrots, celery and garlic in the olive oil or water over medium heat for 5 minutes, until the onions are translucent. Remove from heat and set aside.
Add the chickpeas to a large bowl, and mash with a potato masher (or fork). You do not want them to be completely pasty or mushy, but well broken up. Alternatively, use a food processor, but be careful not to over blend them and make them totally mushy. Pulse a couple of times if using a food processor.
Add the cooked veggies and all the remaining ingredients to the chickpeas. I have found 1 cup of breadcrumbs to be enough, but if the mixture seems really moist, add an extra 1/2 cup. Stir with a large wooden spoon until very well combined.
Press the loaf mixture in the prepared pan, pushing down evenly with your hand. Cover with foil and bake for 30 minutes.
In a small bowl, stir together the ketchup and Worcestershire sauce for the topping.
After 30 minutes, remove the foil, spread the ketchup topping evenly on top of the loaf and bake for another 15 minutes, uncovered. Remove from the oven.
Allow to sit for at least 15 minutes before slicing if you can, it will hold up better. Sprinkle with fresh parsley if desired before serving.