Preheat oven to 350 F. Mix beef and salsa together in a medium bowl. Evenly spread a thin layer of enchilada sauce in the bottom of a baking dish.
Place beef mixture in tortillas with 2 tablespoons cheese. Roll up tightly and place seam side down into the baking dish. Repeat with the remaining beef mixture and tortillas.
Pour the remaining enchilada sauce over enchiladas and top with the remaining shredded cheddar cheese.
Top with diced tomato, diced onion and jalapeno slices. Bake for 20-25 minutes.