01 - Cook pasta in a large pot of salted boiling water according to package directions until al dente. Reserve 1/2 cup of starchy pasta water before draining; set pasta aside.
02 - While the pasta cooks, heat a large skillet over medium-high heat. Add ground beef seasoned with salt and pepper, cooking until deeply browned and no pink remains, breaking it apart with a wooden spoon. Drain any excess rendered fat and transfer the beef to a plate.
03 - In the same skillet, melt the butter over medium heat. Add minced garlic, Italian seasoning, and crushed red pepper flakes. Sauté for approximately 1 minute, stirring constantly, until the garlic is fragrant but not browned.
04 - Return the browned ground beef to the skillet. Add the drained pasta and toss everything together. Gradually pour in small amounts of the reserved pasta water, tossing continuously, until the sauce clings evenly to every strand or piece.
05 - Sprinkle Parmesan cheese over the pasta and toss vigorously until melted and evenly distributed throughout. Taste and adjust seasoning with additional salt and pepper as needed.
06 - Remove the skillet from heat. Scatter chopped fresh parsley over the top and serve immediately while hot.