Preheat your oven to 350°F (175°C). Grease an 8x8-inch baking dish and set aside.
In a food processor, combine the gluten-free oats, almond flour and pinch of salt. Then add the maple syrup and coconut oil or vegan butter for the crust. Pulse until the mixture resembles coarse crumbs and starts to come together.
Press the crust mixture evenly into the bottom of the prepared baking dish. Bake in the preheated oven for 15-20 minutes, or until lightly golden brown. Remove from the oven and set aside to cool slightly.
In a medium saucepan, whisk together the granulated sugar, cornstarch, and turmeric. Gradually whisk in the lemon juice, vanilla and non-dairy milk until smooth.
Place the saucepan over medium heat and cook, stirring constantly, until the mixture thickens and comes to a gentle boil, about 5-7 minutes. Remove from heat and stir in the lemon zest.
Pour the lemon filling over the baked crust, spreading it out evenly. Return the baking dish to the oven and bake for an additional 15-20 minutes, or until the filling is set.
Remove from the oven and allow the lemon squares to cool completely in the baking dish. Once cooled, refrigerate for at least 1 hour to firm up before slicing.
Once chilled, use a sharp knife to cut the lemon squares into squares or bars. Dust with powdered sugar before serving, if desired.
Enjoy your gluten-free vegan lemon squares as a refreshing and tangy treat! Feel free to adjust the sweetness or tartness according to your preference by tweaking the amount of sugar or lemon juice.