Preheat oven to 350 degrees F (175 degrees C). In a large bowl place the ground beef, egg, mushrooms, Ranch seasoning and salt. Mix well to combine. Form into 6 mini loaves and place into mini meatloaf pans. Bake in the preheated oven approximately 30-35 minutes, or until internal temperature reaches 160 degrees F (70 degrees C). Meanwhile make the Ranch Dressing.
Store extras in airtight container in the fridge for up to 4 days.