Put chicken stock in a saucepan and bring to a boil. Add chicken and cook for 6-7 minutes or until meat is cooked. Remove chicken from the stock and shred the meat. Reserve the stock.
Heat olive oil in a nonstick saucepan, sauté onion and garlic until fragrant. Add capsicum and corn kernels, leaving 1 tablespoon of corn kernels aside for use later. Fry for a minute then pour in the reserved stock and bring to a simmering boil.
Leave the cooked broth aside to cool slightly then pour into a food processor in batches to process the broth until smooth.
Return the smooth broth to a saucepan and add the fish slices and the remaining tablespoon of corn kernels. Bring to a boil again and adjust with seasoning to taste. Serve the chowder hot.