For the meatballs:

Preheat oven to 425F. Line a large baking sheet with foil.

In a large bowl and with damp hands, thoroughtly combine the chicken, panko, Pecorino Romano, garlic, egg, parsley, and salt. Form the mixture into 1/2-inch round meatballs (you should have about 36).

Place the meatballs, evenly spaced, on the baking sheet and bake for 20 to 25 minutes, flipping halfway through to ensure even browning. Remove from the oven and set aside.

Cook the pasta: Bring a large pot of water to a boil. Add 2 tablespoons of salt and return to a rolling boil. Add the pasta and cook until al dente according to package directions.

Make the sauce:

Heat the oil in a 12-inch skillet over medium heat. Add the garlic and red pepper flakes and cook until the garlic is pale golden, about 2 minutes. Add the escarole to the pan, tossing it to wilt until it has cooked down. If needed, add scant 1/2 cup of pasta water to help it along. Season with salt and pepper.

Increase the heat under the sauce to medium-high. Ad the pasta and meatballs directly to the skillet and toss to combine with the escarole, adding 1/4 cup of the pasta water or up to 1 cup as needed to loosen the sauce. Stir in the Pecorino Romano and toss again. Plate in bowls; pass extra cheese and hot pepper flakes.