Melt the butter in a large pot over medium heat. Add the chopped bacon and cook, stirring occasionally, until crisp and the fat has rendered, about 8 minutes. Remove the bacon with a slotted spoon and set it aside, leaving the fat in the pot.
Add the white parts of the green onions, celery, garlic, and bay leaf to the pot. Cook, stirring, until softened, about 3 minutes.
Add the reserved corn cobs, chicken stock, and potatoes to the pot. Bring to a simmer, then reduce the heat, cover, and cook for 15 minutes so the broth can soak up all that corn flavor.
Remove the corn cobs and bay leaf and discard. Stir in the corn kernels, bell pepper, creamed corn, salt, pepper, and cayenne. Increase the heat slightly and simmer until the bell pepper is tender, about 8 minutes.
Stir in the cooked bacon, the green parts of the green onions, and the heavy cream. Warm through and serve right away, topped with extra green onion.