Follow directions for heart-shaped parchment package at lower left.
Unfold parchment heart, and coat lightly with cooking spray, leaving a 2-inch border ungreased at edge.
Place 1/2 cup arugula on one side of parchment-paper heart so that it touches fold, but not ungreased border.
Place a chicken breast over arugula; sprinkle with 1/2 teaspoon sage and 1/2 teaspoon rosemary. Top with 1/4 cup tomato.
Sprinkle with one-fourth of salt and black pepper, drizzle with 1 teaspoon olive oil, and top with 1 teaspoon olives, if desired.
Fold paper; seal edges with narrow folds. Repeat with the remaining parchment paper, chicken, and other ingredients.
Place packets on baking sheets.
Bake at 450 for 20 minutes or until puffy and lightly browned. To serve, open packets and transfer arugula and chicken breast to plates; pour juices over top. Or serve right in packets; carefully transfer to plates and pierce each to allow steam to escape.