Nothing clever. I just use the smallest zip lock bag, then put those 2 bags into a third ziplock in my jersey pocket. I tend to roll the individual bags to be sausage shape. Simple and cheap.

https://www.amazon.com/...le?ie=UTF8&psc=1

I like these, but to each their own.

I stumbled across these at Hobby Lobby probably 5 years ago or so and have been using them ever since. I use them to hold 2.5 scoops of Tailwind (250) calories both on the bike and when doing ultra running events/training. I’ve never tried it but they should hold 3 scoops fine. I don’t think they’d hold much more than that though.

https://www.hobbylobby.com/...-2%22-x-3%22/p/12076

I have used 'fill-n-go funnels' with no issues for quite some time. There's a bunch of them from different companies, but the concept is all the same. Reusable, cleans up easy in the dishwasher, no leaks, etc. Easy to pour into and the bottom of the funnel will pour into even the narrowest bottle opening. A little goofy shape for a jersey pocket, but I haven't found anything better.

These aren't the specific ones I have, but they look nearly identical.