Prepare a grill for indirect heat. If using a charcoal grill, build the hot coals on one side only. If using a gas grill, heat one side only to medium-high heat. Place a cooling rack over indirect heat. Place a heavy-bottomed saucepot over direct heat.
Slice the tomatoes in half. Drizzle them with olive oil and season with salt and pepper. Place the tomatoes on the cooling rack on the grill, cut-side down, to soften and take on some smoke while you make the sauce, 10 to 12 minutes.
Meanwhile, add a drizzle of olive oil to the saucepot along with the bacon. Cook, stirring occasionally until the bacon is crisp, 3 to 5 minutes. Stir in the garlic, onions and crushed red pepper flakes if using and cook until the onions soften, an additional few minutes. Add the wine. Tie the fresh herbs together with a piece of butcher's twine and add to the saucepot.
When your tomatoes have begun to soften, remove them from the grill. Remove the skins (they will come off really easy), add the tomatoes to the saucepot and season with salt and pepper. Close the grill and continue to cook the sauce until the tomatoes fully break down and the sauce thickens slightly, about 20 minutes.
Meanwhile, bring a pot of salted water to a boil. Cook the pasta 2 minutes less than the package directions. Using tongs, pull the pasta out and add it directly to the tomato sauce, along with 1/3 cup of the starchy pasta water. Mix to combine. The sauce will stick to the pasta. Remove the saucepot from the heat.
Add the butter and a drizzle of olive oil to the pasta and stir to combine. Add the basil and and stir again. Serve with freshly grated Parmesan over top.
(Alternatively, you can cook the sauce and pasta over medium-high heat on a stovetop.)