Remove husk from corn, trim and cook in a large pot with plenty of boiling salted water for about 30-40 minutes. Meanwhile, rinse tomatoes and cut into cubes. Rinse bell peppers, cut in half, remove seeds and ribs and cut into cubes. Rinse parsley, shake dry, pluck leaves from stem and coarsely chop.
Peel onion, trim and cut into thin strips. Remove corn from the boiling water, rinse with cold water and cut kernels from cobs with a sharp knife. Mix all ingredients except tortilla chips together in a bowl and season with salt and pepper. Shortly before serving, add half of tortilla chips, mix and season to taste. Spread corn salad over 4 plates and serve with remaining tortilla chips.