Hot outside, treat ideas?

Hi all! We have a 7 month old husky/labradoodle mix and a 6 year old husky. It is currently 94 F right now, but feels like 109 F. This will probably be average for the rest of the summer. They go outside, potty, and chill for 5-10 minutes to make sure they have time to pee and poop. Any ideas for non-messy good treats to help them cool down? Puppy likes the kong and I know I can freeze it, but my adult girl doesn’t like the kong, yogurt, peanut butter, veggies, and I can’t use bananas because I’m allergic. Anything I can freeze that’s not too messy? I put ice cubes in their water bowls once a day and make sure they have water outside all day.