Cook the pasta according to the instructions and set aside in a colander.
Heat a skillet over medium high heat. Season the chicken with the salt and pepper.
Add to the skillet and cook for about 4 minutes per side, or until juices run clear (internal temperature should be 160 degrees).
Remove and let cool. Once cooled, slice the chicken into pieces.
Add the diced ham to the skillet and cook about 3-5 minutes, or until the edges are browned and caramelized. Remove and set aside.
Heat the butter in a skillet over medium heat. Add the garlic and cook until it just starts to brown, about 1-2 minutes.
Add the chicken and ham and cook for another 1-2 minutes.
Add the white wine to deglaze the pan and cook for 2-3 minutes.
Add the chicken broth and Dijon mustard and bring to a simmer. Simmer for 5 minutes.
Add the cream and bring to a simmer. Season with additional salt and pepper if desired.
Add the pasta and stir until sauce coats it. Remove from heat and stir in the cheese.
Notes
Cook the fettuccini so it's al dente (has just a tiny but of bite to it).
If your sauce is too thick, add some additional chicken broth to thin it out just a bit.
Substitute chicken breast for chicken thighs (the results will be slightly less juicy).
Season the sauce with additional salt and pepper after tasting if needed. Everyone has a different salt preference, so I try to cook my recipes with the minimal amount of salt. Adjust it to your taste.
The internal temperature of the chicken should be 160 degrees when fully cooked. Typically, 4-5 minutes per side is enough.