2/3 cup drained oil-packed sun-dried tomatoes, coarsely chopped
1/3 cup oil-cured black olives, pitted and coarsely chopped
1 teaspoon dried oregano
Freshly ground pepper
1 pullman loaf (20 slices) of white bread
Extra-virgin olive oil, for brushing
10 thin slices provolone cheese
1 pound fresh mozzarella, cut into 1/4-inch slices
In a food processor, combine the sun-dried tomatoes with the olives and oregano. Season with pepper and process to a coarse paste.
Lightly brush 1 side of each slice of bread with olive oil and set on a large baking sheet, oiled side down. Top half of the bread with the provolone, spread each slice with 1 tablespoon of the tomato-olive pesto and top with the mozzarella. Close the sandwiches with the remaining bread, oiled side up.
Heat a griddle or a very large skillet. Arrange 3 or 4 sandwiches on the griddle and top with a cast-iron skillet: do not press the pan down. Cook the sandwiches over moderately high heat until golden on the bottom, about 2 minutes. Flip the sandwiches and cook until browned and the cheese is melted, about 2 minutes longer. Transfer to a wire rack to cool. Repeat with the remaining sandwiches.
Cut the crusts off the sandwiches, then cut into triangles and serve.
The panini can be prepared through Step 3 and stored on a wire rack at room temperature for up to 6 hours. Reheat on a baking sheet in a 350° oven until crisp.
For an even more flavorful sandwich, brush the bread with the oil from the jar of sundried tomatoes. Strain the oil first through a sieve to remove any small bits that would burn on the griddle.