Finely chop the onion and the celery. Peel the potatoes and then cut them into cubes roughly 1 inch in size. Place the prepared vegetables to one side.
Chop the chicken breasts into roughly 1 inch chunks, and slice the bacon into small pieces.
Heat the oil in a large, deep pan to a medium-high temperature, and then fry the bacon for 5 minutes until it is cooked and golden. Remove the bacon from the pan using a slotted spoon and set to one side.
Reduce the heat of the pan to medium and add the chopped onion and celery to the pan. Allow them to gently fry in the bacon infused oil for roughly 5 minutes until they are beginning to soften.
Add the chicken to the pan, along with the crushed garlic cloves, the dried oregano, the dried thyme, and salt and pepper, to taste. Cook the chicken for 3 to 4 minutes until it is just beginning to color.
Add the flour to the pan and throughly stir it in, and then add the chicken stock and the cream, and finally the chopped potatoes. Allow everything to simmer together until the potatoes are just soft and the chicken is cooked though; this should take 10 to 15 minutes.
Add the corn to the pan, along with half of the cooked bacon, stir it in and allow everything to cook for a few minutes longer.
Serve the chowder hot, sprinkled with the remaining cooked bacon and the chopped scallions.