MAKES 9 SQUARES
Ingredients
Crust
• ¾ cup coconut flour
• ⅓ cup palm sugar
• 3 tablespoons tapioca flour
• 1 teaspoon grated lemon zest
• ½ teaspoon baking powder
• ¼ teaspoon salt
• 4 tablespoons coconut oil
• 1 tablespoon coconut milk
Filling
• 1½ cups palm sugar
• 2 large eggs, plus 2 large egg whites
• 4 tablespoons coconut flour
• ⅔ teaspoon salt
• 2 tablespoons grated lemon zest
• 12 tablespoons lemon juice (4 lemons)
• 2 tablespoons palm sugar
• Coconut oil for greasing foil
Preparation
1. Adjust oven rack to middle position and preheat oven to 350°F. Make a foil sling for an eight-inch square baking pan by folding two long sheets of aluminum foil so each is eight inches wide. Lay sheets of foil in pan perpendicular to each other, with extra foil hanging over edges of pan. Push foil into corners and up sides of pan, smoothing foil flush to pan. Grease with coconut oil.
2. Process flour, palm sugar, tapioca flour, lemon zest, baking powder, and salt in a food processor until combined (about 10 seconds). Add coconut oil and coconut milk and pulse until mixture resembles coarse meal (about 10 pulses). Transfer mixture to prepared pan and press firmly into an even layer using a wide metal spatula. Bake until edges are lightly browned (16 to 20 minutes), rotating pan halfway through baking. Let cool on wire rack for at least 15 minutes.
3. Reduce oven temperature to 325°F. Whisk palm sugar, eggs, egg whites, flour, and salt together in bowl until smooth. Stir in lemon zest and juice. Pour filling over baked crust. Bake until filling is set (15 to 20 minutes). Let bars cool completely in pan on wire rack for about one hour.
4. Remove from pan using foil sling, cut into nine squares, and sprinkle with palm sugar. Serve.
