I've used these simple tart shells for tartlets like you see above and for full sized pies and tarts. I actually modified the recipe from a multigrain cracker recipe I found on the web.
You bake the shells first so they stay crispy when filled and guess what... they taste like shortbread cookies! I wasn't looking to make a gluten free desert shell, but my GF friends are certainly glad I did.
They really are simple... you do have to watch them in the oven though... they brown quickly.
Use a whisk to mix together the almond flour, sugar, and salt.
Add the melted butter to the flour mixture and stir until the the butter is fully combined. The flour will take on the consistency of wet sand. It may take several minutes so I use solid wooden spoon.
Add the beaten egg to the flour mixture. Stir with the spoon for a bit but the dough will get thick quickly, and the consistency will quickly resemble Play-dough. So do what you did as a kid, dive in with your hands and work the dough until the egg is mixed throughout.
For my 2 inch tartlet shells I use a ball of dough larger than a quarter, but smaller than a ping-pong ball. I get about 30 tarts per batch of dough. I butter my tart shells for easy release after baking. I press each ball of dough into the shell until it's about 1/8 inch thick.
I do the same for pie shells and full size tart shells. For those I will also roll it out with a rolling pen on parchment paper and then flip it over onto the pie tin and peel the paper back. Whatever method, I keep the thickness about the same so my cooking time stays consistent.
Bake your shells in an oven preheated to 300 degrees for about 20 minutes. You with the shells to be slightly brown, but not much more than medium brown. The taste of almond flour begins to change dramatically as it browns and goes to burnt quickly. An even light brown is what you are looking for.
If you will be baking the filling that is going in you pie or shell, then you might want to go with a little lighter bake as the edges will brown more during the second baking.
For tartlets or tarts remove the shells from the tins after cooling. I whack the back of the tin with a sturdy spoon to release the stubborn ones.