Position a rack in the lower third of the oven and preheat to 325 degrees. Prepare the spoon bread: Cook the bacon in a skillet until just crisp; transfer to a paper-towel-lined plate with a slotted spoon, leaving the drippings in the pan. Grease a 6-cup shallow baking dish with some of the drippings and dust with 2 teaspoons cornmeal. Place on a baking sheet.
Add the milk to the remaining drippings in the skillet and bring to a boil over high heat. Whisking constantly, gradually pour in the remaining cornmeal. Add 1 teaspoon salt, the sugar and cayenne. Lower the heat and simmer, whisking, until thickened, about 3 minutes. Stir in the corn, scallions and bacon; remove from the heat.
Beat the eggs with a mixer until very pale and fluffy, about 5 minutes; add the baking powder. Stir a quarter of the whipped eggs into the cornmeal mixture, then carefully fold in the rest. Pour the batter into the prepared baking dish; bake until puffed and golden, about 50 minutes.
Prepare the tomatoes: Toss the tomatoes, olive oil and herbs in a bowl with salt and black pepper to taste; set aside for at least 5 minutes. Let the spoon bread rest 10 minutes; serve with the tomatoes.