Set out three low bowls. In the first bowl mix the flour with 1 tsp of the salt. In the second bowl whisk the milk, hot sauce, and eggs. In the third bowl combine the cornmeal, bread crumbs, garlic powder, paprika, black pepper, cayenne pepper, and the remaining 1 tsp salt.
First, dredge the tomatoes in the flour mixture, then in the egg mixture, and then in the cornmeal mixture. Place the tomatoes on a plate as you finish each one.
Prepare the grill for direct cooking over medium heat (350°–450°F) and preheat a grill-proof griddle.
Place the bacon on one side of the griddle and the onion slices, bell pepper planks, and jalapeño halves on the other side. Close the lid and grill over direct medium heat, with the lid closed, until the bacon is crisp, the onion is tender, and the bell peppers and jalapeño are charred, 10–12 minutes, turning once or twice. Remove from the griddle, place the bacon on paper towels to drain, and put the onion slices, bell peppers, and jalapeño in a bowl.
Clean off some of the excess bacon drippings from the griddle and coat the griddle with the 2 tbsp vegetable oil. Place the prepared tomatoes on the griddle and cook over direct medium heat, with the lid closed, until golden brown, 10–12 minutes, turning once. Remove from the griddle and place on paper towels to soak up any excess grease.
Adjust the grill’s temperature to medium-low heat (250°–350°F).
Butter the bread on both sides. Grill the bread slices on the griddle over direct medium-low heat, with the lid closed, until golden brown, 3–4 minutes, turning once. Remove the bread from the griddle.
Using a food processor blend the onions, bell peppers, and jalapeño until smooth. Add the cream cheese and blend until evenly incorporated. Add the jar of pimentos and, using the pulse function, pulse all the ingredients together allowing the pimentos to remain slightly chunky. Transfer to a large bowl and add the cheeses, mayonnaise, garlic powder, and salt and pepper to taste. Give everything a good stir.
Apply a layer of the pimento cheese spread on two slices of bread. Top each with two fried green tomatoes, three bacon slices, and two lettuce leaves. Next, add another bread slice to each sandwich, apply a layer of pimento cheese spread, and add two more fried green tomatoes, three more bacon slices, and two more lettuce leaves. Spread the final two bread slices with pimento cheese and place on top of the sandwiches, cheese side down. Cut each sandwich in half and serve right away.
