Preheat oven to 450 degrees F (230 degrees C). Oil a 12×15 inch pan with olive oil.
Place salt pork in a large, deep skillet over medium heat. Cook until evenly brown, stirring occasionally. Stir in 1 chopped onion, and continue cooking until onion is tender and lightly browned; set aside.
Meanwhile, in a large bowl, combine potatoes and remaining chopped onions. Fill the bowl of a food processor with the mixture, and 1 egg. Process until smooth, then transfer to a large bowl. Repeat until all has been processed. Season with pepper. Stir in the salt pork mixture. Blend in flour gradually to absorb some moisture, but err on the side of less flour.
Bake in the preheated oven for 25 minutes. Reduce heat to 350 degrees F (175 degrees C), and continue baking for 1 hour, or until top is evenly browned.