Boston Baked Beans

Add the dried beans to a large bowl, cover with cold water, and soak overnight.
Drain the beans and add them to a large pot with the garlic, celery, bay leaves, carrot, and half of the white onion (left whole). Fill the pot with water, covering the beans by about 2 inches.
Bring to a boil over high heat, then reduce the heat to low and cover with an offset lid. Simmer for approximately one hour or until the beans are tender, not mushy. As the beans simmer, check periodically and skim off any foam that forms on the surface.
Once tender, remove the spices and whole ingredients from the beans.
Preheat the oven to 300 degrees Fahrenheit.
Heat a large oven-safe pot or Dutch oven over medium-high heat. Sauté the second half of the onion (diced) and the bacon until the bacon is partially cooked and the onion is translucent then mix in the brown sugar, molasses, ketchup, mustard, salt, and pepper until completely combined
Carefully transfer the beans and cooking liquid to the oven-safe pot or Dutch oven containing the bacon and onions. Mix to combine.
Cover the pot with aluminum foil and transfer to the preheated oven. Check the beans occasionally and stir gently, making sure they don't dry out. If needed, add a bit of water or broth.
Bake the beans for 2 ½-3 hours, or until the beans are tender and the sauce has thickened significantly.
Garnish with fresh parsley if desired.