Cut chicken into 1/2 inch pieces. Mix together in a medium bowl all the spices, chili powder through salt. Add the diced chicken and stir to coat throughly.
Heat large pot of water to boiling and add pasta, cook according to package directions. You can start the alfredo while it's cooking. When done, drain, but do not rinse.
Heat olive oil on medium high in a large deep skillet. Add chicken and saute until the chicken starts to brown on the outside and cook for about 3 minutes. Add the garlic and cook another 1-2 minutes. Add butter and heat until melted. Stir in flour and cook for another minute. Stir in the half & half and heat until it starts to thicken. Add the fettucine and stir until throughly mixed. Divide onto plates and top with shredded parmesean