I’ve recently started using these 4 fl oz reusable silicone pouches from Stasher to carry one typical serving of DIY fuel mix. What you see in the photo is approximately 60g dextrose and 35g fructose. There’s room for a little more.
I can fit 2 into a aero jersey pocket, that’s enough for me. My bottles already have fuel in them.
I refill my bottle with water, dump the fuel mix in, and shake. Then I put the empty Stasher bag back in my pocket.
No more single-use bags and it’s dishwasher safe.
Having weighed my ingredients once, I know how many scoops of each ingredient to put into my bottles and pouch(es), so I make them up very quickly before rides or the night before.
That’s all. You can get them from lots of places and in 2-packs; wherever saves you money.