Preheat the oven to 350 F and prepare a rectangle 14.4"x 5.9" (or similar in size) tart pan with non-stick spray.
Place all the crust ingredients into a food processor and pulse until a dough forms. Press the dough evenly up the sides of the tart pan and the bottom.
Place the tart pan on a baking sheet and bake the crust for 12-14 minutes or until golden brown. The crust might seem too stiff and over baked but it will soften up as it chills with the filling.
While the crust is baking, zest your lemons and then juice them. Whisk together the juice, zest, eggs, egg yolks (TIP: Save the egg whites for future recipes), sugar, dairy-free butter, lavender and salt into a pot or large saucepan.
Cook until the mixture thickens, about 4-6 minutes stirring frequently. Once the curd has thickened and coats the back of a spoon, pour it through a fine mesh strainer to remove all the chunks and then transfer the smooth curd to the tart and use a spatula to spread it evenly.
Cover and chill the tart in the refrigerator for at least two hours or preferably overnight.
Top with desired toppings and serve!
If you don't have a fine mesh strainer, be sure to whisk the curd continuously to avoid clumping. Your curd won't be as smooth but it will work.
The pan used is 1.5" deep, if yours is not as deep, consider cutting the curd recipe in half.