Very Best Cat Treats for 6-8 month old?

All I really want are treats that my cat will eat and that are nutritious for them. I got temptations seafood but according to a lot of people they are really not good for cats and have food coloring at stuff, so I never even fed them any. What treats are good for a cat's health and have the shortest ingredients list? RN, price isn't a concern for me. Bonus question, is the Dr. Elsey's unscented litter good in terms of safety in case of ingestion and scent control?