Heat oven to 325℉.
Line a sheet pan with parchment paper. Set aside.
In a medium bowl, combine sugar and lemon peel.
Use your fingers to rub the peel and sugar together.
Add butter.
Beat with an electric mixer until light and fluffy, about 2-3 minutes.
Mix in flour and salt.
Turn out onto a non-stick surface (parchment paper, silicone mat, marble board).
Cover with a piece of parchment.
Roll to ⅜ inch thick.
Use a 2¼" scalloped cookie cutter to cut out. (If you haven't used any flour to roll out the dough, you can gather the scraps and re-roll.)
Place on prepared baking sheet.
Top each cookie with an edible flower.
Press down lightly to hold in place.
Bake for 12-13 minutes, or until just starting to color around the edges.