Making the Lemon Curd

1. In a small saucepan, whisk together plant milk, sugar, cornstarch, salt, and lemon zest.
2. Heat over medium heat, whisking constantly, until it starts to thicken.
3. Reduce heat and cook for about 1 minute until the mixture is silky and pudding-like.
4. Take off heat and whisk in lemon juice and dairy free butter. Cover with plastic wrap pressed onto the surface and chill until cold.

Preparing the Lemon Cookie Dough

1. Cream together dairy free butter and sugar until fluffy.
2. Mix in lemon zest and lemon juice.
3. In a separate bowl, combine gluten free flour, cornstarch, baking powder, and salt.
4. Gradually add dry ingredients into the wet ingredients, mixing until soft dough forms.
5. If the dough is too dry, add plant milk 1 teaspoon at a time. If too sticky, add flour and chill for 30 to 45 minutes.

Shaping and Baking Cookies

1. Roll the dough between two pieces of parchment paper to about 1/4 inch thick.
2. Cut out cookies and chill on the baking sheet for 10 minutes before baking.
3. Preheat oven to 350°F and bake for 10-12 minutes until edges look set but not browned.
4. Cool on rack before assembling.

Assembling the Sandwich Cookies

1. Once cookies are cool, flip half over and place 1-2 teaspoons of lemon curd on the center.
2. Top with remaining cookies gently to spread the filling close to the edges.