Melt the butter in a pan.
While it is melting, cut your chicken breasts in half. Be careful not to brown or burn the butter.
Sear chicken on both sides, but don't let it cook all the way through yet.
Add in chicken broth, tomato paste, lemon juice, and spices. Stir well. Let it come to a boil before reducing to low heat and covering.
Let simmer for about 45 minutes, stirring occasionally. If the sauce starts to thicken too much, add a little lemon juice and/or chicken broth.
After about 30 minutes, you can start to break up the chicken to ensure it cooks all the way through.
Cook pasta according to box directions while letting the chicken and sauce still simmer.
The chicken should be thoroughly cooked about the same time the pasta is done. Be sure to check before serving.
Serve chicken and sauce over pasta and enjoy!