Spray or line your 5-8 qt slow cooker.
Chop your potatoes into 1 inch pieces and add them to the slow cooker. Top the potatoes with minced garlic and chicken broth.
Nestle the frozen Jennie-O turkey breast in the oven bag into the center of the potatoes.
Cover and cook on low for 6 hours.
Remove the turkey in the oven bag and add any juices from the turkey bag to a small saucepan. Let the turkey rest on a cutting board so the juices can settle in.
Being careful with the hot liner of the Crock Pot, pour off any liquid in the pot into the saucepan with the turkey juices. Add the gravy packet to the juices and cook over high heat until it is bubbling and thickened, stirring occasionally.
To the pot of potatoes, add the cream cheese, milk, garlic salt and and butter. Mash the potatoes until smooth, being careful not to over process or they will be gummy.
Slice up the turkey breast and serve with the potatoes and gravy.