With a sharp knife, carefully cut the kernels from the cob. Set aside.
If you want to make corn stock, put the cobs into a saucepan and add enough cold water to cover. Simmer for 10-15 minutes.
Heat the butter in a skillet over medium-high heat. When it's foamy, add the corn, tomatoes, onion, and scallion. Pour in the stock and add the basil. Reduce the heat and simmer for 3-4 minutes, or until the vegetables taste done and moist but are no longer soupy.
Ladle the succotash into individual bowls, and top with pan-seared filets of beef if wanted. (Take 4 6-oz beef filets, salt and pepper, brown in olive oil to caramelize, finish in a 400 degree oven for 4-5 minutes. Use the same pan for the succotash.)