In small bowl, combine flaxseed meal and water. Mix and set aside for 5 minutes.

Combine flour, baking soda, baking powder, sugar, ginger, cinnamon, nutmeg, cloves, white pepper and salt in a large bowl. Whisk to combine and remove lumps.

Add flax mixture, molasses, oil, milk and vanilla to the flour mixture. Stir to combine.

Preheat oven to 350 degrees F. Line baking sheet with parchment paper. Scoop 1 tablespoon of batter onto the sheet, spacing cookies 2 inches apart.

Bake 5–10 minutes, rotating pan after 5 minutes. Cookies should puff up and set. Insert a toothpick to check doneness. Cool cookies on wire rack.

In medium bowl, combine softened cream cheese and butter. Mix with a spatula until smooth. Add powdered sugar and mix well.

Microwave chocolate chips in 30-second intervals, stirring to melt. Add melted chocolate and vanilla to the cream cheese mixture and stir until combined.

Spread filling on the bottom of half the cookies. Top with remaining cookies.

Chill for 30 minutes. Dust with powdered sugar before serving.