Preheat your oven to 325°F (163°C). In a large mixing bowl, sift together the all-purpose flour, corn starch, baking powder, and lemon zest until well combined.

In another mixing bowl, beat together the unsalted butter and shortening with sugar using an electric mixer on medium speed for 3-4 minutes until light and fluffy.

Add one room-temperature egg, along with the vanilla extract and almond essence, to the creamed butter mixture and beat until smooth.

Gradually add the sifted dry ingredients into the wet mixture, mixing on low speed until just combined.

If your cookie dough feels too soft, wrap it in plastic wrap and chill it in the refrigerator for 15-20 minutes.

On a lightly floured surface, roll out the chilled dough to about 1/4-inch thickness and use bunny-shaped cookie cutters to cut out the cookies.

Place the cut-out cookies onto parchment-lined baking sheets and bake for 9-10 minutes.

Allow the cookies to cool on the baking sheets for about 5 minutes before transferring them to wire racks.

In a medium bowl, beat together softened butter and sifted powdered sugar until smooth, then gradually add vanilla extract and milk.

Once the cookies are fully cool, pipe the buttercream frosting onto each bunny cookie and decorate with sugar sprinkles and black sugar pearls.