Gluten-Free Crust:

1. Blend flour, coconut sugar, and salt together in a large mixing bowl or food processor. Cut in or blend in shortening/butter until mixture is crumbly. Blend in lemon juice/vinegar and water 1 tablespoon at a time, just until dough comes together and is soft, but not sticky. Dough shouldn’t be crumbly, if it is add a little more water until it’s pliable.
2. Roll dough out in between 2 sheets of parchment paper (to prevent sticking) a couple inches larger than your pan (mine is a 10.25-inch tart pan).
3. Invert the crust into the tart pan using the parchment paper. Carefully fit the dough into the pan, along the corners and up the edge. Fold in excess dough to reinforce the sides then trim any extra dough. Prick the bottom of the crust and place into the fridge or freezer to chill. Meanwhile, preheat the oven to 375ºF.
4. After the dough has chilled for 15–20 minutes, line the crust with parchment and fill with pie weights or dried beans. Place pan onto a baking sheet and bake for 25 minutes. Remove pie weights and parchment and bake for an additional 10–15 minutes until golden brown. Let cool completely before filling. Crust can be made 1–2 days ahead of time, cooled completely, and loosely wrapped in plastic wrap. Assemble the tart shortly before serving.

Vanilla Custard:

1. Pour 1 1/2 cups milk into a medium saucepan. In a separate dish, whisk together remaining 1/2 cup milk and the cornstarch to make a slurry. Stir in sweetener and salt.
2. Slowly pour slurry mixture into the pot of milk and whisk until well blended.
3. If using a vanilla bean, cut it lengthwise done the center and use the back of your knife to scrape out all of the seeds. Stir the seeds and the vanilla bean pod into the milk mixture.
4. Place saucepan over medium heat and bring to a simmer, whisking often to avoid clumps.
5. Custard will thicken as it cooks. Watch it closely and stir often as it can burn easily. Adjust heat as needed.
6. After a couple minutes of cooking and stirring, the mixture should begin to thicken, like pudding. It will thicken more as it chills, but when it’s ready it should be thick enough to coat the back of a wooden spoon. If custard gets too thick, just stir in a splash more milk.
7. Turn off the heat and stir in vanilla.
8. Strain cream, to catch any lumps and vanilla bean, through a fine-mesh sieve into a bowl. Place plastic wrap directly onto the surface of the custard to prevent a skin from forming. Refrigerate until fully chilled, several hours or overnight. Can be made 1–2 days in advance and refrigerated until ready to use. Before using, whisk again until smooth.

Putting it Together:

1. Pour chilled custard into the cooled tart shell (remove shell from the pan before filling) and smooth the top with an offset spatula.
2. Decorate the top with fresh berries or other fruit of choice. Chill for 30 minutes and serve. Best if eaten within a few hours of assembling. Store leftovers in the refrigerator.
3. Inspired by this tart from marthastewart.com