Cut chicken breasts in half, width-wise to create 4 chicken cutlets. Season both sides of each chicken breast with salt and pepper.
Place flour on one plate. Whisk the egg and milk on another plate. Combine bread crumbs, Italian seasonings, garlic powder, and salt onto a third plate. This is your breading station.
Dredge a chicken breast in the flour, dip it into the egg/milk mixture, then coat it in the bread crumb mixture. Place prepared chicken breast on a plate and repeat with remaining chicken breasts.
In a large saute pan heat olive oil. Gently place breaded chicken breasts into the oil. Cook on medium-low heat for 5 minutes on EACH SIDE, until brown, crispy and internal temperature reaches 165 degrees Fahrenheit. Remove chicken from pan and place it on a cooling rack that has been placed inside of a baking tray. Place the tray of chicken in a warm oven to keep it hot and crispy while you work on the sauce
Add garlic to the pan that you cooked the chicken in. Saute for one minute or until fragrant. Add chicken broth, diced tomatoes, half and half, parmesan and Italian seasonings. Whisk constantly until mixture comes to a boil.
In a small dish, whisk the cornstarch and COLD water. Add the cornstarch slurry to the boiling sauce and whisk until the sauce returns to a boil and thickens up. Season additionally with salt and pepper.
Serve chicken and sauce over a bed of cooked, whole wheat spaghetti noodles.