Apr 20, 2021 · How long should you bake chicken breast? The cooking time will depend on the size of your chicken breast and also on the power of your oven. Some ovens have slight heat differences. But according to USDA, a 4-oz. chicken breast should be bake at 350°F (177˚C) for 25 minutes or 30 minutes. Apr 02, 2018 · Tips! Letting the chicken breast marinate in milk for 20 minutes helps break down enzymes so that the meat becomes more tender. It’s common practice to soak chicken in milk when making Southern-fried chicken, although sometimes it’s marinated overnight. 20 minutes is enough for this easy recipe.