- Make the marinated tomatoes: In a bowl, combine tomatoes, shallots, olive oil, basil, and vinegar. Set aside for at least 8 hours, or overnight.
- Make the succotash: Preheat oven to 350 degrees. Roast corn in its husk for 12 minutes, then set aside until cool enough to handle. Shuck corn and cut kernels from cobs, reserving cobs. Set kernels aside and add cobs to a pot with heavy cream and crème fraîchè. Bring mixture to a boil, then adjust heat to maintain a simmer for 10 minutes. Remove from heat, strain and reserve liquid, and discard cobs.
- In a large pan, cook bacon over medium heat until golden and crispy. Add butter, onion, and garlic. Cook until softened and onion is translucent. Add peas, corn kernels, and cream mixture and cook for another minute. Season with salt and pepper, remove from heat, and stir in herbs. Set aside and keep warm.
- Make the basil oil: In a blender, combine basil and ¼ cup olive oil. While blender is running, slowly drizzle in remaining oil and blend until smooth. Pour the mixture through a fine mesh strainer lined with a cheesecloth and discard the solids. Set aside.
- Make the fish: Preheat a grill to 400 degrees. Season grouper with salt and pepper, then transfer to grill. Cook until fillets reach an internal temperature of 145 degrees.
- Divide succotash into bowls. Divide crab meat into bowls. Add a grouper fillet to each. Top grouper with marinated tomatoes and a drizzle of basil oil.