1. For the diced and drained tomatoes: Seed and dice about 3 cups of fresh, high-quality tomatoes. Toss them with a little kosher salt and sugar. Set over a colander while you prepare the remaining ingredients if possible. If not, drain for a minimum of an hour. You should finish with about 2 cups of tomato.
2. For the roasted tomatoes: Seed and dice 4 cups of fresh, high-quality tomatoes. Toss them with olive oil, plenty of kosher salt, and several sprigs of thyme. Spread this mix out on a baking sheet and roast at 350 degrees for about 30 minutes. You want the tomatoes to be dry and slightly caramelized, but not burned around the edges. You should finish with about 2 cups of roasted tomato.
3. For the Onions: Peel and slice (with the grain) 3-4 large/medium yellow onions. In a large sauté pan, heat 1/2 cup butter. Add the onions and season them with salt. Let the onions simmer and become juicy. Once the situation becomes a bit drier and much of the onion liquid has cooked out, turn down the heat, to its lowest setting and settle in for a long, slow caramelize. To get these onions where they need to be, it could take about 2 hours. You are looking for a medium brown, sweet caramelization.
4. To Assemble the Filling: Combine the onions, fresh tomatoes, roasted tomatoes, basil, salt, pepper, and sugar to taste. Keep in mind, tomatoes take a lot of seasoning to really make them shine in applications like this.
5. To Bake and Serve: Spread the filling over the bottom of a blind-baked crust. Flatten the topping between wax paper or use your good ol’ hands to create a 1/3 inch thick round of delicious, cheesy topping that spreads nearly to the edges of the pie. Bake at 375 degrees until the top is nicely browned...20-25 minutes. Serve at just over room temperature.