@Gnotknormal, have you tried other powder foods before? Especially maltodextrin-based ones, like Joylent, Jake and the lot?
As @Julian puts it, maltodextrin-based ones will have less texture. It might be a good place to start since that will build a positive feedback loop about the slightly powdery milk-shakey feel in the mouth and the nutrients it brings. Maybe later on you could try Huel again and it won’t feel that wrong. Although I appreciate I might be wrong about how this works with autism.
As @Ric said, there’s not much you can do to change the texture of Huel. And I agree that a blender won’t help except for the lumps.
However it might be worth giving the vanilla fravoured version a try still. Since the difference in weight between one and the other is ~200g of something, it does dilute the chalkiness a bit (not too much though).
IIRC there’s the £4 mini-pouch you can try and get a £4 discount on a later order if you find that works for you.
I think I will try the vanilla one for sure. I don’t know of other maltodextrin shakes. What even is maltodextrin? I have had food replacement shakes (like Complan), they didn’t have the dusty chalky texture but they tasted very very sweet which I didn’t like.
@Gnotknormal Maltodextrin is a carbohydrate that is cheap but which has a high Glycemic Index, which means it raises your blood sugar quickly. Huel uses oats as the main source of carbohydrate, which has a lower GI.
That doesn’t sound good to be honest. Might as well be surviving on sugar if it’s going to have the same effect, surely? I don’t think it’s a good idea to survive on a ‘food additive’
Adding nut milk to Huel makes the texture silky smooth. I would recommend hazelnut milk. Do consider the added nutritional profile if you try it.
Nut milk like almond milk? I haven’t ever tried that, but I just may do! I have soy milk and haven’t tried Huel with that yet - worth a shot I think. 
Yes, almond milk works great too. I don’t think soy milk would have the same effect but it might be nice in it’s own right. I do strongly recommend hazelnut milk though if you like it - absolutely delicious.
Have never tried hazelnut milk. Hazelnuts are my least favourite nut but I’m happy to try anything really
@Gnotknormal, just to make it clear: I’m not recommending maltodextrin-based meal replacements as a permanent, well, meal replacement. I am fully aware of the GI of maltodextrin (I even posted a comparison between Huel, Sugar and Joylent a while ago See my glucose variation in my blood after eating Joylent and Huel). I was merely stating my opinion that using those (temporarily) might improve your perception of Huel.
I am also aware that talking about maltodextrin and alternatives to Huel on this forum seems to be perceived as disrespectful 
So sorry everyone.
Thanks for clearing that up. I think I’m just going to have to keep experimenting and see what I come up with
Actually, if you go to Reddit, or even Soylent’s (capital S) discourse, talk about different products is encouraged. Rob Rhinehart, the creator of the first Soylent, open-sourced from the beginning. Their discourse has a whole topic for DIY, where people can compare recipes and get feedback. You’ll find honest dialog (and even favorable reviews) of other products. The theory being, the more one soylent product is embraced by the public, the more receptive people will be of alternatives.
If anyone is interested, check out Reddit. Lots of good feedback and insights about all 20+ soylent brands.
Actually, that’s true. I started by going to the Soylent discourse a while back and got into trying out my own recipes on the DIY site. I gave up eventually though because I couldn’t get my recipe quite right. But it was a good experiment and a good resource.
Probably very late and you’ve already made your decision - but I have a similar issue to you (OP) and have found the blender, vanilla doesn’t make a difference. I think your best shot is something someone above has mentioned - yogurt. So far I’ve only tried just spooning in a little to my yogurt and mixing it and it basically went unnoticed. I’ve not yet tried a high density mix.