Preheat oven to 375 degrees F. Line baking sheets with parchment paper.

To make flax “eggs,” in small bowl, combine flaxseed meal and water. Let rest for 5 minutes to thicken. Set aside.

In medium bowl, whisk together flours, baking powder, salt and cardamom. Set aside.

In large bowl, cream butter and sugar with electric mixer 3 minutes, or mix manually until light and fluffy.

Beat in flax “eggs,” vanilla, almond extract and lemon zest, if using.

Add flour mixture in two batches, beating on low speed until combined, or mixing manually until well combined.

Shape dough into disk and wrap in plastic wrap or cover with kitchen towel. Chill 1 hour, or until firm.

With rolling pin, roll out half of dough to 1/4-inch thickness on floured work surface.

With 2-inch cookie cutter or shape cutters, cut out cookies and arrange about 1 inch apart on baking sheets. Repeat with remaining dough. Brush cookies with coconut oil, then sprinkle with sugar. Place 1 large pinch of chopped nuts in center of each cookie, and press lightly.

Bake 8 to 10 minutes or until edges start to brown. Transfer to wire racks to cool.