Blend garlic powder, onion powder, seasoned salt, rosemary, thyme, and paprika in a blender into a fine powder; pour over ground beef in a large bowl. Knead seasoning mixture into the beef. Roll beef into balls and arrange into a glass baking dish.
Bake meatballs in preheated oven for 20 minutes. Pour marinara sauce over the meatballs and continue baking until hot and grey in the center, about 25 minutes more. An instant-read thermometer inserted into the center should read 160 degrees F (70 degrees C).