In skillet over med-high heat, brown the sausages, breaking it up as you brown them. Drain off any fat. Reserve 1 tbsp of the sausages. Spread sausages into bottom of casserole dish.
Place cheese and tomatoes w/ chiles in a microwaveable bowl. Microwave in 15 second intervals, stirring until melted and combined. Spread cheese mix over sausages. Place top oven rack 6" from heat. Place casserole dish on top rack. Broil until cheese turns golden. Sprinkle w/ reserved sausages. Serve w/ tortilla chips.