Sauté pancetta in olive oil over medium heat until crisp, about five minutes.
Drain the pancetta on a paper towel, reserving the fat in the pan.
Add the next four ingredients and sauté for about six to eight minutes, stirring often and making sure that the mixture doesn't stick to the pot.
Sprinkle the flour over the mixture and stir for one to two minutes.
Add a little milk to scrap the bottom of the pot clean.
Gradually add the rest of the milk, stirring constantly. Bring to boil, reduce heat to medium low and cook until slightly thickened about five minutes.
Add the clams with their juice , salt and pepper and cook for about five to ten minutes, until the vegetables are done.
Add the corn and pancetta and turn off the heat.
Let the soup steep for a few minutes.