The coconut oil or diary-free shortening for the dough should be chilled but not hard. If you do not want a thick border crust simply skip folding the edges and spread the filling out from the center to cover more area.
Ingredients
For the dough
¾ cup brown rice flour
¾ cup sorghum flour
½ cup tapioca starch/flour
½ teaspoon xanthan gum
½ teaspoon salt
9 tablespoons coconut oil or dairy free shortening chilled no more than 5 minutes
⅛ cup thyme
6-8 tablespoons cold water, as needed
For the filling
1 medium white onion thinly sliced
¾ cup black olives pitted and sliced
1 tablespoon thyme
2 tablespoons unsweetened soy or coconut yogurt
2 teaspoons olive oil plus more to drizzle
3 garlic cloves pressed
2 teaspoons chopped shallots for garnish (optional)
Salt and pepper to taste
Instructions
Preheat oven to 350 F
Line baking sheet with parchment paper
Combine flours, xanthan gum and salt
Add coconut oil or shortening in wide chunks on top of flour mixture
Cut coconut oil or shortening into flour mixture with a pastry cutter or fork
When mixture is crumbly add 4 tablespoons of cold water
Add thyme
Continue to cut ingredients and add additional tablespoons of water as needed until a dough forms
Cover dough with plastic wrap and refrigerate while preparing filling
In a separate bowl mix onions, olives, thyme, yogurt, olive oil, pressed garlic and salt and pepper
Lightly flour countertop or dough mat
Take dough from refrigerator and separate into two equal-sized disks
Roll each disk with a rolling pin until you have thin round layers about 10 inches in diameter
Gently lift crusts with a spatula and place on baking sheet
Spoon equal parts of filling in the center of each crust
With your hands fold over the edges of the tart to form a border
Bake 35-40 minutes until crust and onions are browned
Let cool for 5 minutes
Top with chopped shallots and a sprig of thyme (optional)
Drizzle with olive oil and serve
Crust adapted from Living Without, December/January 2013 pg. 53 recipe by Food Allergy mom Colette Martin. Instructions' language for crust were slightly adapted
Recipe by Kitchen to Nirvana at https://kitchentonirvana.com/2013/03/05/onion-black-olive-thyme-tart/