1. Heat olive oil in a large Dutch oven over medium-high heat. Add 2 cups onion, carrot, and celery to pan; sauté for 6 minutes, stirring occasionally. Stir in peas; sauté for 1 minute. Add broth and the next 4 ingredients (through ham hock); bring to a boil. Reduce heat, and simmer 1 1/2 hours or until peas are tender, skimming surface occasionally, as necessary.
2. Remove ham hock and bay leaves; discard. Remove salt pork; cool. Remove 1 1/2 cups pea mixture; let stand 5 minutes. Puree 1 1/2 cups pea mixture, and return to pan, stirring to thicken slightly. Stir in parsley, chopped thyme, salt, and pepper.
3. Dice salt pork. Heat a nonstick skillet over medium-high heat. Add pork to pan; cover and cook 5 minutes or until crisp and browned, stirring frequently. Ladle 1 cup soup into each of 8 bowls; top each serving with 1 tablespoon pork and 1 1/2 teaspoons crème fraîche. Sprinkle with fresh thyme leaves, if desired.