01 - Whisk together lemon juice, lemon zest, sugar, cornstarch, coconut cream, turmeric, and salt in a small saucepan until smooth. Place over medium heat and cook, whisking constantly, until mixture thickens and just begins to bubble, about 3-4 minutes. Remove from heat, transfer to a bowl, and let cool completely. Refrigerate to thicken further.
02 - Beat coconut oil and sugar in a large mixing bowl until light and creamy. Add applesauce, lemon zest, lemon juice, and vanilla extract; mix until combined. In a separate bowl, whisk together gluten-free flour, almond flour, cornstarch, salt, and baking soda. Gradually add dry ingredients to wet ingredients and mix to form a soft dough. Divide dough in half, shape into discs, wrap in parchment, and chill for 30 minutes.
03 - Preheat oven to 350°F. Line two baking sheets with parchment paper. On a lightly floured surface, roll dough to 1/4-inch thickness. Cut into rounds about 2 inches in diameter. Place cookies on prepared baking sheets, spacing 1 inch apart. Bake for 10-12 minutes, or until edges are just golden. Cool completely on wire racks.
04 - Spread 1-2 teaspoons of vegan lemon curd onto the flat side of half the cookies. Top with remaining cookies to form sandwiches. Dust with powdered sugar if desired.