Ingredients

2 1/2 teaspoons extra-virgin olive oil
3 ounces pancetta or nitrate-free deli ham, diced
1 medium yellow onion, peeled and chopped
1 cup chopped celery
1 pound freshly shelled peas, or frozen baby peas
4 cups shredded romaine lettuce (use inner leaves)
3 1/2 cups low-sodium chicken or vegetable broth, plus extra for thinning
Salt and pepper