Heat a grill, grill corn (for fritters and topping) until slightly charred and cooked, about 10 minutes. Remove from cob.
Heat about 1/4 inch of canola oil in a cast-iron skillet to 375 degrees,
In a large bowl combine corn, green onion, onion, garlic, salt, flour and egg. Gently fold in lump crab meat, trying not to break up the pieces. If batter is too wet, add more flour 1 tablespoon at a time until the mixture can be formed into fritters or patties.
Using a 1/4 cup measure, scoop out and form into flat fritters. Fry 3-4 at a time in the oil, about 1-2 minutes per side or until golden brown. Drain on paper towels.
In another bowl, combine cherry tomatoes, remaining corn, basil and crab meat. Season with salt and pepper.
To assemble, top each fritter with a heaping tablespoon of ricotta, then top with corn, tomatoes and crab.