For the corn broth: Shuck the corn and shave off the kernels. Reserve ears in an 8-quart stockpot and cover with water. Bring to a boil, reduce heat and simmer for 1 hour. Strain to reserve the liquid; discard cobs.
For the creamed corn: Place a large saucepot over medium-high heat; add butter and onions, and then sauté mixture for 3 minutes or until translucent. Add corn and flour; stir to blend well. Add 2 cups corn broth, whisk briskly and bring to a boil. Let simmer for 15 minutes. Pour in whipping cream and bring to boil. Reduce heat and simmer for 20 minutes or until smooth and thickened. Season with salt and pepper. Serve.