If you are looking for a enamelled/metal storage solution this ‘cookie’ jar works very well. It takes a full size bag, with about an inch to spare. Its got a rubber airtight seal around the lip. The edges are curved and it doesn’t scratch readily so its really easy to clean.
For bonus points, you take the “Cookie” label out and write which kind of Huel it contains on the other side, which is really useful if you have both vanilla and unsweetened.