Prepare the flax eggs and let them sit in the fridge for 30-60 minutes.
Preheat oven to 350 F and prepare two baking sheets with silpats.
In a bowl, beat together the butter and brown sugar until creamed. Add in the flax eggs, oats, flour, yeast, flax, baking powder, soda, salt, vanilla, lemon zest and 2 tablespoons of poppyseeds.
Scoop out a 2-tablespoon ball of cookie dough and roll into a ball. Flatten out onto the silpat. The cookies require a lot of space to spread, so you'll likely want to put 8 per pan. Repeat with the other pan. I do two batches, so that's equal to 4 pans depending on the size of your pans. Sprinkle with the remaining 1 tablespoon of poppyseeds.
Bake in the middle of the oven for 14-15 minutes, or until lightly golden around the edges.
Allow the cookies to cool on a cooling rack.
Meanwhile, in a bowl, mix together the powdered sugar with lemon juice and transfer to a piping bag. Drizzle the cooled cookies with the lemon glaze. Enjoy and happy nursing mamas!