Bake French fries according to package directions. Keep warm.
Heat the oil in a skillet over medium heat. Sauté the pastrami until browned and crispy, about 8 minutes.
Slice the bread open lengthwise without cutting all the way through it.
Heap the pastrami onto the bottom half of the bread. Top with coleslaw, tomatoes, and then with French fries. Season with salt and pepper. Press the sandwich down slightly and cut it into 4 pieces. Serve immediately.