In a large bowl, beat the buttery spread, organic cane sugar, powdered sugar, and lemon juice on medium speed until light and fluffy.
Add the gluten free flour blend, lemon zest, and poppy seeds and mix on low speed to combine. (If the dough seems too wet, add a bit more flour. Texture can vary with different gluten free flour blends).
Divide the dough into two parts, and shape into discs. Wrap the discs with plastic wrap or waxed paper and refrigerate for one hour.
Preheat oven to 350 degrees F. Line two cookie sheets with parchment paper.
Lightly flour a rolling pin and rolling surface with gluten free flour. Place the dough on the surface and roll to about a ¼ inch thickness. (If the dough is too cold and stiff, you may have to let it warm up just a little bit before rolling.
Using a round cookie cutter, (or a different shape if you prefer) cut out cookies, and quickly transfer them to the cookie sheets.
Bake at 350 degrees F for 12-14 minutes.
Cool for a few minutes on the cookie sheets, then transfer to a wire rack to cool completely.
Repeat steps 5-8 with the remaining dough.
Once the cookies are cool, place the ½ cup of powdered sugar in a fine mesh sieve and dust it over the cookies.