Step 1If ground poppy seeds are unavailable, grind them in a blender or coffee grinder. Place them in a small saucepan and add the milk, honey, raisins, butter and lemon juice. Cook over medium heat, stirring frequently, until most of the liquid is absorbed, 10 minutes. Remove the pan from the heat, cool the filling slightly, then cover and refrigerate it until firm, about 2 hours. (You can make this up to three days ahead).
Step 1Cream the butter, brown sugar and honey in the bowl of a mixer on medium speed. Beat in the eggs, 1 at a time, and the vanilla, scraping down the sides occasionally.
Step 2Sift the baking powder, baking soda and all-purpose and whole-wheat flours together, discarding excess bran, if any, and blend into the butter mixture. Form the dough into two disk-like shapes and wrap them in plastic wrap or wax paper. Refrigerate the dough for several hours until firm. (This may be made up to three days ahead).
Step 3Heat the oven to 350 degrees.
Step 4Roll out 1 disk of the chilled dough on a lightly floured surface to 1/8 inch thick. Keep the other half in the refrigerator until ready to use. Use a large round cookie cutter, wide-mouthed glass or clean tuna can with the bottom removed to cut out circles. Place a teaspoon of the filling in the center of each circle and pinch the edges to form a triangle, leaving a small opening in the center to see the filling.
Step 5Place the cookies about 1 inch apart on a baking sheet lined with parchment paper. Bake them until the cookies are lightly browned, 12 to 14 minutes. Remove and cool on a wire rack.