Cook the penne pasta according to the package instructions.
You'll want to make sure it's al dente to hold up with the sauce.
Drain and set aside when cooked.
Trim any excess fat or skin from the chicken and pat it dry with paper towels.
Sprinkle the Cajun seasoning generously on both sides for a good kick.
In a skillet, melt butter over medium heat.
Place the seasoned chicken breasts in the pan and cook for about 5-6 minutes on each side, or until fully cooked.
Remove from the pan and set aside.
In the same pan, reduce heat and add heavy cream and lemon pepper seasoning.
Stir occasionally and let the mixture simmer until it begins to bubble slightly, giving a thick texture.
Slice the cooked chicken into strips.
Mix the pasta with the creamy sauce and top it with the chicken, diced tomatoes, and grated Parmesan cheese.
Serve it up hot!