In a large skillet over medium heat, brown sausage until fully cooked. Transfer sausage crumbles to a slow cooker and add tomatoes with green chilis, shredded cheese and cream cheese.
Cover and turn slow cooker to low for about an hour, stirring occasionally until all is melted and combined. Once completely combined, serve in a bowl or in the slow cooker on warm.
I prefer to serve this straight from my slow cooker on warm so that it says gooey melted. If the dip starts to stiffen up, you can reheat in intervals in the microwave or turn the slow cooker back to low. Be sure to stir often so that it doesn't burn.