In a large skillet with high sides that is broiler-safe, melt 1 tablespoon of the butter. Add the panko and cook, stirring very often, until it is golden and toasted, 1 to 2 minutes. Remove to a small bowl. Wipe the skillet clean.
Add the remaining 1 tablespoon butter and heat over medium high. Once the butter is melted, add the chicken. Sprinkle with the Italian seasoning, garlic powder, salt, and pepper. Cook on all sides until the chicken is golden brown and cooked through, about 4 minutes. Remove to a separate plate or bowl.
Add the oil and garlic. Cook, stirring constantly, just until fragrant, about 30 seconds. Pour in marinara sauce, water, and vinegar. Bring to a strong, steady simmer (not a rolling boil) and stir in the pasta. Cover the pot. Cook until the pasta is al dente, about 11 to 15 minutes depending upon the shape of your pasta. Check the pot several times throughout and stir to make sure the pasta isn’t sticking to the bottom.
Stir in the chicken. Slowly add the mozzarella a handful at a time, stirring between each to make sure it's melted before adding the next so the cheese incorporates evenly. Stir in 1/4 cup Parmesan. Taste and adjust the seasoning as desired.
Prod the pasta into an even-ish layer. Sprinkle with the reserved Panko and remaining 2 tablespoons Parmesan. Broil until the top is lightly crispy, 1 to 2 minutes. Sprinkle with fresh basil. Let cool for a few minutes, then dive in.
Notes
TO STORE: Transfer chicken Parmesan pasta to an airtight storage container and store it in the refrigerator for up to 4 days.
TO REHEAT: Warm up leftovers in a skillet set over medium-low heat or in the microwave.
TO FREEZE: Transfer the pasta to a freezer-safe storage container or ziptop bag and store it in the freezer for up to 3 months. Let it thaw in the refrigerator before reheating according to the instructions above.