For the sauce: Place the ketchup, brown sugar, syrup, vinegar, Worcestershire, pepper and garlic in a small pot. Bring to a low boil, reduce the heat to low and thicken 15 minutes. (This sauce stores well for weeks and makes a tasty sloppy Joe, burger baster and pork chop topper if you want to double the recipe. If using for a more all-purpose BBQ sauce, add 1/2 cup chicken stock and simmer for 20 minutes.)
For the chowder: Heat the EVOO in a soup pot over medium-high heat and add the bacon, if using. Cook until crisp 2 to 3 minutes. Add the potatoes, corn, celery, onions, bell pepper, chile, garlic, thyme, seafood seasoning and bay leaf, and stir. Cook to soften, 8 to 10 minutes. Add the beer and cook the beer down by half, 1 to 2 minutes. Add the beans, tomatoes, shredded chicken, BBQ Sauce, stock and 2 cups of water. Simmer a few minutes to combine the flavors, cool and store for a make-ahead meal. Reheat over medium heat.
When ready to serve, peel, pit and dice the avocado and dress it in the lime juice. Place diced avocado and some broken tortilla chips in each soup bowl, top with the hot chowder and serve.