Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper.
In a mixing bowl, whisk together the all-purpose flour, almond flour, baking powder, baking soda, cornstarch, salt, and lemon zest. Set aside.
In another bowl, cream together the softened vegan butter and granulated sugar until light and fluffy, using either a hand mixer or a stand mixer.
Add the lemon juice and the vanilla extract to the butter-sugar mixture, and mix until well combined.
Gradually add the dry flour mixture to the wet ingredients, mixing until a soft dough forms. If desired, add natural yellow food coloring or substitutes to achieve a vibrant yellow hue, adjusting the amount according to your preference.
Using a cookie scoop or spoon, portion out the dough onto the prepared baking sheet, leaving some space between each cookie for spreading.
Flatten each ball of dough slightly with your fingers or the back of a spoon.
Bake in the preheated oven for 10-12 minutes, or until the edges of the cookies are lightly golden brown.
Remove the cookies from the oven and let them cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.
Once the cookies are completely cool, you can dust them with powdered sugar for an extra touch of sweetness, if desired.