1 lb (2 cups) green or yellow split peas
1 small onion, peeled and chopped
1 tsp thyme leaf
1 tsp kosher salt
1/2 tsp fresh black pepper
2 Tbsp of your favorite hickory-smoked barbecue sauce
5-1/2 cups water
Place all ingredients in a 3-1/2- or 4-quart slow cooker. Set to HIGH and cook for 4 hours.
After 4 hours, stir the soup. The split peas should have broken down to make a chunky soup with great consistency. Taste and adjust for seasoning (more salt, more pepper, more BBQ sauce). If you want a smoother soup, transfer the contents of the slow cooker to a food processor (in batches, if necessary) and pulse to desired smoothness.
If you're adding smoked turkey chunks or cooked sausage, stir it in after the soup has reached the desired consistency.
To make the croutons: Cut 2-3 slices of challah (or brioche) into 1-inch cubes. Toss with a bit of olive oil, and sprinkle with sea salt. Toast in a frying pan over medium heat, shaking the pan frequently, until the croutons are crisp on all sides.
Serve the soup hot, topped with croutons.