Soak the dry beans overnight in a bowl of warm water.
Add the seasonings to a pan. Meanwhile, cook the beans over medium heat until soft, but firm, and drain.
Add the ketchup, apple cider vinegar, stock and Worcestershire sauce to the pan and bring it to a boil.
Add the drained beans to the pot and continue cooking until the beans turn softer. Now add the cornflour slurry, give it a quick mix and take it off heat once it thickens.
Notes
Check the beans at the 45 minute mark to see if they're soft. If you feel they're still tough, you can add half a teaspoon of baking soda into the liquid to help them soften.
You can also pressure cook the beans to make things quicker.
Reserve a bit of the liquid after you've cooked the beans. This starchy liquid can help the sauce cling to the beans nicely and also thicken the sauce.