01 -
Lightly coat your grill pan with cooking spray and cook the chicken until done, about 2-3 minutes each side (timing depends on how thick they are). Take them off and let them cool a bit.
02 -
Throw basil, pecorino cheese, pine nuts, garlic, olive oil, salt, and pepper into a food processor. Pulse until everything's mixed and the basil turns into a smooth paste. You'll end up with roughly ⅓ cup.
03 -
Smear pesto on both bread slices. Stack chicken, tomato rounds, and mozzarella on bottom half, then cap with the other bread piece. Do this for all your sandwiches.
04 -
Give both sides of each sandwich a quick spray. Pop it in your panini maker or grill pan, shut the lid, and push down to get those nice grill lines. Cook until the bread turns golden and cheese gets all melty.