Slice chicken breasts horizontally to create thinner cutlets, about 0.5-inch thick, for even cooking. Pat the chicken dry with paper towels – this helps achieve that great blackened crust. Rub both sides generously with the blackening seasoning. Meanwhile, get a large pot of salted water heating up for your pasta.

Heat the olive oil in a large skillet (a cast iron pan works wonders here!) over medium-high heat until it's shimmering. Add the seasoned chicken and cook for 4-5 minutes per side, or until it's deeply browned, crusted, and cooked through (the internal temperature should reach 165°F). Remove the chicken from the skillet, tent it loosely with foil, and let it rest while you finish the dish.

By now, your large pot of salted water should be at a rolling boil. Add the fettuccine and cook according to package directions until it's perfectly al dente. Before draining, make sure to scoop out and reserve 1 cup of that starchy pasta water – it's your secret weapon for a silky sauce!

Don't clean that skillet yet! Those browned bits from the chicken add amazing flavor. Return the skillet to medium heat and melt the unsalted butter. Add the minced garlic and cook for just 1 minute until it's fragrant, being careful not to let it burn.

Pour in the heavy cream and bring it to a gentle simmer, stirring occasionally. Reduce the heat to low. Gradually whisk in the freshly grated Parmesan cheese until it's smooth and completely melted into a beautiful, velvety sauce. Season with black pepper and salt to taste. If the sauce seems a little too thick, add a splash of that reserved pasta water to reach your desired consistency.

Slice the rested blackened chicken into bite-sized strips. Add the drained fettuccine directly to the Alfredo sauce in the skillet, tossing gently to coat every strand. If needed, add a tiny bit more reserved pasta water to make sure everything is beautifully coated and saucy. Top with the sliced blackened chicken, garnish with fresh chopped parsley if you like, and serve immediately. Enjoy!