Place the peas in a large pot or bowl, cover with water by 2 inches and soak 8 hours or overnight. Drain the peas and set aside.
Score the ham hock. Place in a pot, cover with water and bring to a boil. Reduce heat and let simmer for 1 hour. Drain and set aside.
In a large pot, melt the butter over medium-high heat. Add the onions and cook, stirring, for 2 minutes. Add the celery and carrots and cook, stirring, until just soft, about 3 minutes. Add the garlic and cook, stirring, for 30 seconds.
Add the ham hock and ham and cook, stirring, until beginning to brown. Add the drained peas, salt, pepper, and pepper flakes, and cook, stirring for 2 minutes. Add 8 cups of water, the bay leaf and thyme, and cook, stirring occasionally, until the peas are tender, about 1 hour. (Add more water as needed, if the soup becomes too thick or dry.)
Remove the bay leaf and discard. Adjust the seasoning, to taste, and serve immediately with Parmesan Truffled Chips on top.
Parmesan Truffled Potato Chips:
Using a mandolin or very sharp, heavy knife, slice the potatoes into rounds as thin as possible, and place in a large bowl of water to prevent discoloration.
Heat the oil in a large, heavy pot to between 340 and 350 degrees F.
Pat the potatoes completely dry. Add to the oil in batches and cook until golden brown, stirring with a long handled spoon to turn and cook evenly, about 2 minutes. Drain on paper towels and place in a large bowl. Toss with the cheese, truffle oil, salt, and pepper. Serve immediately.