Maquechoux is a traditional Cajun dish. Every Southern cook has her own version; the one constant ingredient is corn.
Scrub oysters well with a brush under running water. Discard any that are open or have broken shells. Shuck oysters, saving all liquid and bottom halves of shells. Scrub shells inside and out, and set aside. Refrigerate oysters in reserved liquid, covered, until ready to use.
Cut corn from cobs; set aside. Heat oil in a medium saute pan over medium-low heat. Add onion and cook, covered, until translucent, about 10 minutes.
Add corn and cook, stirring, for about 5 minutes, or until corn is softened. Add salt, cayenne, red pepper, and jalapenos and cook for 2 minutes.
Drain oysters, reserving liquid. Measure liquid and add enough water to make 1 cup. Pour into pan. Turn heat up to medium and cook about 10 minutes, or until liquid is mostly reduced. Set aside.
In a large skillet, heat about 1 inch of oil to 375 degrees. Dredge oysters in cornmeal, coating them entirely. Fry in batches (don't overlap) and drain on paper towels.
Arrange 4 or 5 oyster shells on each plate. Spoon about 1 teaspoon of Red Pepper Mayonnaise into each shell, and top with an oyster and some of the corn mixture. Serve immediately.