What are shells? 

Different than pierogi in the flavor and filling.  Pierogi have potatoes or potatoes and cheese inside.  I have never made them, so don't know if or how the dough may differ when making them homemade.  I make them thinner, dough wise, than commercially made pierogi I have had.

Yes, when we made them in ds's preschool class, many years ago, it was just flour and warm water.  and the dough was pretty stiff/dry, but not as dry as pasta dough.  Just a bit more pliable.  And thicker in the center as you roll them, so once folded, it is all even, basically.  The center does not get doubled up like the edges. 

This is the recipe I used.  I just did a search for vegan wonton wrappers.

http://low-cholesterol.food.com/recipe/vegan-wonton-wrappers-281598

I have a recipe from a cookbook of recipes from China (not Americanized recipes) that calls for just water and flour to make the dumplings.  I remember the measurements were off and I think I had to add a lot more flour to make it work.

It calls for 10 oz flour and 8-12 oz very hot water.  That's almost a 1 to 1 ratio of flour to water and I think that's way too much water.  But you do want more water than you would put into a bread-type recipe. 

I know the right consistency by feel and am not sure how to explain it well.  You make a ball of dough with flour and water (mix and need) and then take very small amounts of dough and roll them out.  You want to roll from the center of the dough outward and keep turning the dough on a well-floured surface so the center is slightly thicker than the rest, if possible.  If that's too complicated, you can just press your small ball down flat a bit and then roll it out with a roller.  You want it thin but not so thin it will break when you try to stuff it or so thick it won't hold together well when you fold it.  Usually homemade skin is a bit thicker than commercial.

Which allergens do you deal with?  We use Twin Marquis brand.  They are made in the USA and contain just wheat, water, corn starch, salt, and sodium benzoate.  I called the company about allergens and felt the were safe for our allergy-set since DS is doing baked for several allergens now.  I am not as worried about xcontam with those two allergens.  The other allergens DS has were not in their facility.

 

Yes

Per request from ajas.

I referenced this recipe  but changed a few things.  I used a 20oz pack of ground turkey, then the garlic, ginger, 2 thinly sliced scallions, some Tamari, sesame oil,an egg, in about the recommended measures. 

I used Nasoya wrappers.  Either the square wonton ones or round dumpling ones work.  I seemed to have an easier time making the round ones pretty this time. 

When I cook them, I drizzle a small amount of olive oil into a non stick skillet, add about 1/4 c. water, and then place the dumplings on the pan.  Cover, then let them steam until the water is gone.  Then, uncover and let them get brown on the bottom.  I place on wax paper or parchment(before and a clean piece after cooking). 

I make a dipping sauce with some of the tamari, sesame oil, seasoned rice vinegar, minced or crushed clove of garlic and some grated ginger and sliced scallions, and brown sugar to taste. 

http://allrecipes.com/recipe/chinese-pork-dumplings/