Cut chicken breasts in half lengthwise, to form 2 cutlets. Season with 1/4 tsp salt and 1/4 tsp pepper. Heat a large skillet over medium high heat. Coat pan with non stick spray. Add chicken, and cook for about 4 minutes on each side, until cooked through.
In a small food processor combine artichokes, 3 Tbls Parmesan cheese, pine nuts, mayo, olive oil, garlic, 1/4 tsp salt, and 1/4 tsp pepper. Pulse until coarsely ground.
Lightly toast slices of bread in a toaster, under a broiler, or over a grill.
To serve spread 2 1/2 Tbls artichoke pesto on each slice of bread. Top with 3 oz of sliced chicken, sprinkle over remaining Parmesan cheese and garnish with parsley. Sprinkle with a few crushed red pepper flakes if using.