Make the muhammara: Put the red peppers, pecans, panko, garlic, lemon juice, salt, red pepper flakes, cumin, olive oil, and pomegranate molasses into a food processor fitted with a metal blade. Pulse until finely chopped, nearly to a puree, scraping down the sides as needed.
Assemble the sandwiches: Lightly toast the bread in a toaster. Spread a few tablespoons of the muhammara on four slices of bread. Divide the chicken over the muhammara and top with a pile of arugula. Lightly drizzle with olive oil and cover with remaining bread.
