When this core of charcoal and coal/coke is thoroughly lit, add more green coal and fill the fire pot.
     As this new and large volume of fresh coal ignites, there will be copious amounts of smoke produced. This is normal but not uncontrollable. Use a poker to knock a hole in the top center of the fire, allowing flames from the core to escape. The flames will ignite the volatile components of the smoke and burn a significant portion of it away.

Please Note: The center of the fire has virtually no smoke (see photo). The center is where the coke is located, and coke burns cleanly. The area around the core is creating a fair amount of thick smoke. This is the green coal igniting and burning.