Working off of Rebecca Reilly's recipe for Filo Dough - from her book Gluten Free Baking - I decided that if filo could be achieved, then so too should puff pastry. I made a lot of changes and substitutions including: argar argar instead of gelatin, potato starch instead of all rice flour and sugar instead of honey.
Warning - I am purposefully not tagging this as a recipe because this was my first attempt and scroll down to the bottom to see my comments about how I would change MANY ingredients and techniques for next time.
Gluten Free Puff Pastry (take 1)
1 1/2 cups sweet rice flour
1/2 cup potato starch
4 tsp xanthan gum
1 tsp argar argar
1 tsp sugar
1 egg
1/4-1/2 cup water
1 stick of unsalted butter, melted
1. Mix dry ingredients together, for a well.2. Mix the wet ingredients together - make sure to break up the egg.
3. Add additional water if needed to form a soft dough that is cohesive. (more wet than pie crust, more like a dough)
4. Wrap and refrigerate overnight.Day 2
In preparation for rolling the dough and layering in the butter, I found this video extremely helpful.
Take 2 sticks of unsalted butter and knead them together into a rectangle.The butter needs to be at the same temperature and consistency as the dough, so its important that the butter in thickness as possible. To do this, I borrowed a friend's technique of kneading the butter under cold water (in a bowl). This made the butter pliable without it melting. It is very important to dry the butter thoroughly before trying to add it to the dough.

After working it under the cold water and patting it dry, I placed it between two sheets of plastic wrap to help even out the shape and to be able to easily transfer it onto the dough.
Set the butter aside.
Working between two sheets of plastic wrap*, roll out the dough to about 1/4" thick. It needs to be large enough to completely wrap the butter.*I am a huge fan of parchment paper, but for this plastic wrap is best. This dough will stick to parchment and you will spend too much time fiddling with it trying to pry it off the dough and time is your enemy right now. You need to keep everything cold.
Place the butter near the center of the dough.
Fold the dough over the butter, overlap is not a bad thing, you need to completely envelope the butter.
Fold the other side of the dough over the butter.
Fold the bottom of the dough upwards.
Fold the top of the dough down. Now its really important for you to check your seams and make sure that there is dough everywhere and no butter poking out. The dough is not what a gluten-based one would be like; its similar to a slightly gummy pie dough. It will break and crack but you can patch it together.
Place another sheet of plastic wrap atop the dough and with a rolling pin, push downward making and X-shape across the dough. Then use the pin and push down on the dough horizontally and vertically - you are trying to smoosh the layers together - before you start rolling.
Then begin rolling the dough out. You want to keep the rectangle shape.Notice here that the butter started breaking through. THIS IS BAD. Puff pastry only puffs when there are layers of dough-butter-dough throughout the mixture. If the butter layers start touching you are running into pie dough territory, not puff pastry.
Next time, I would refrigerate the butter and dough package before attempting to roll it out. Giving it time to ensure that the butter and dough were at the same temperature.
In trying to keep the butter layers from touching, I generously sprinkled the dough with sweet rice flour. And continued rolling.
So right now there is one mass with three layers: dough-butter-dough. The process of adding more layers is called "putting in turns" and its all about taking those three layers and layering them atop one another and making more layers - the more layers, the more flaky the dough.
You are going to make two folds, cutting the dough in thirds and stacking each atop the other - like folding a business letter.
Fold the top third down.

Fold the bottom third up, covering the top third.

Turn the folded dough 90 degrees, so it faces you so it looks like the opening of a book.
Then proceed to roll out the dough again into a rectangle.

This is the completion of 1 turn.
You can see that there is still some butter poking through - again, this is NOT a good thing.

Follow the same steps of folding the dough in thirds and then turning it 90 degrees and roll it out again.

*It is really important to keep an eye on your plastic wrap and lift it up from the dough pretty often. As the dough is rolled and stretched, so too is the plastic wrap and it will break and tear. For this whole process I went through 2 sets of plastic wrap.

Second turn complete.
Then refrigerate for at least an hour.

Putting in the third turn.
I then put it in the fridge to rest.
After removing it from the fridge and putting in the 4th turn, I then rolled it out and cut off an edge piece and baked it off. (At this point I thought that too much butter and made its way through the dough and I had ruined the batch and was not ready to put in more time rolling if it was going to be a blob and not flake.)
But it did puff and flake!

But the dough lacked salt. This was something I was worried about from the get-go, but thought maybe it was unnecessary. I was very wrong.

So I ground up some table salt and sprinkled it on the dough and put in a 5th turn.
You can see the dough is looking a lot more homogenious now. No visible butter breaking through. Working with very cold dough takes a lot longer - it is very hard and takes a while to roll out - but I think it might be the trick to preventing the butter from escaping.I left it here, about 1/2" thick and wrapped it and put it in the fridge to rest overnight.
DAY 3
The dough was very cold and equally difficult to roll out. (Hence less photos because I spent that time mumbling under my breath that I should be more patient and let the dough warm up and I would struggle less. But I digress.)

I decided on an apple tart and I rolled the dough out to between 1/4" and 3/8" thick. I cut a rectangle and then strips to run around the edges. I glued the edges together with egg wash, placed sliced apples in the center, brushed the top of the edges with more egg wash and sprinkled sugar over everything.
I constructed everything on an upside down cookie sheet lined with parchment.
I placed it in a 400F oven for 40 minutes total.
(I started with just 20 minutes and checked on it every 5 minutes until the edges were golden brown.)
You can see that the sides should have been a little wider but they puffed and browned!While not the most beautiful thing I have ever made, I have never been prouder of something I baked. I served it up with a quick homemade caramel sauce, not pictured here.

Ideas for next time
-The pastry has a very distinct rice flour taste - a different blend of flours might help. Perhaps tapioca starch, more potato starch and some corn starch and much less rice flour.
-Maybe a full tablespoon of sugar in the initial dough.
-Definitely salt is needed in the dough, maybe 1/2 a tsp?
-Work the dough and butter together when they are cold, don't put more than 2 turns in at a time; refrigerate between each time.
-Maybe up the argar argar to prevent the dough from cracking when rolling it out when its so cold. (I am not sure if this would work) Or roll the dough out thinner and do two additions of butter in stead of one.
-The bottom dough was chewy and a little flaky, but the outer crust was much better. This recipe might work best for shells that are filled after they are baked rather than for tarts or turnovers.

















