These are the signature bar of The Dirty Apron deli. Typically, they bake them gluten-free by substituting an all-purpose gluten-free flour mix. They recommend being extra patient when whipping the eggs--don't be afraid to go at it. That's the secret to the moist, creamy texture. I halved the original recipe, as it called for a 12x16" sheet pan that I didn't have, and instead baked them in an 8x8" glass dish. Although I somewhat regret that decision--after typing up this blog post, my mouth is watering for more and I wish I had leftovers! I opted to make my own "pistachio paste" as it can cost around $20 for a pre-made container. I made my own by grinding pistachios in a coffee grinder with the sugar and water to the consistency of thick peanut butter. Super easy!