Rinse the beans and drain. Sort any unwanted debris and set seasoning packet aside.
In a 6qt crockpot, add the beans, broth, ham bone (if using), onion, garlic, and chili powder in a 6qt slow cooker. Do not add lemon or tomatoes until the beans are softened.
Cook on high for 5 hours (or low for 7-8) or until the beans are tender.
Once the beans are tender, remove the ham bone (if using), chop any meat left on the bone, and add it back to the slow cooker.
Stir in the diced tomatoes, ham seasoning packet, and lemon juice.
Cook for an additional 30 minutes. Season with salt and black pepper to taste and garnish with fresh parsley if desired.