If you are using bacon, cut it into small pieces and cook it slowly in a medium pot over medium-low heat. If you are using a ham hock, heat the oil in the pot. Once the bacon is crispy (or the oil is hot), increase the heat to medium-high and add the celery, onion, and green pepper and sauté until they begin to brown, about 4-5 minutes. Add the garlic, stir well and cook for another 1-2 minutes.

Add the black-eyed peas, bay leaf, thyme and Cajun seasoning and cover with 4 cups of water. If you are using the ham hock, add it to the pot and bring to a simmer. Cook for 30 minutes to an hour, or longer if needed, until the peas are tender but not mushy.

While the black-eyed peas are cooking, cook the rice separately according to package instructions.

When the peas are tender, strain out the remaining cooking water. Remove and discard the bay leaf. Taste the peas for salt and add more if needed. If using a ham hock, remove it from the pot, pull off the meat, and return the meat to the pot.

Serve the dish either by placing a ladle-full of black-eyed peas over steamed rice, or by mixing the two together in a large bowl. Garnish with chopped green onions. Serve immediately.