Preheat the oven to 350 degrees F. Line mini cupcake pans with 48 mini cupcake liners.

In the bowl of a stand mixer with the paddle attachment, mix the oil and sugar on high speed until creamy and fully incorporated. Mix in the crystallized ginger until fully incorporated. Add the egg whites and mix well. Sift together the flour, baking powder, ground ginger, and salt in a large bowl. On medium speed, add the flour mixture alternately with the milk and vanilla mixture until combined. Do not over-mix. Fill the cupcake liners three-quarters of the way and bake for 15 minutes.

To assemble: Using a pastry bag fitted with a small round tip, pipe the top of the cupcakes in a dot pattern with Lime Buttercream, creating 6 dots to cover the tops of the cakes. Snip a small cluster from the stem of each branch of the micro herbs. Place the bunches in the center of the icing. Zest fresh lime zest over the cakes to finish off the garnish

Place the lime juice and cornstarch in a small pan on the stove. Cook over medium heat, whisking, until the mixture thickens. Transfer the lime curd to a silicone mat and refrigerate until cool, about 5 minutes. In the bowl of a stand mixer with the paddle attachment, cream the butter and salt. Add the cooled lime curd. Add the confectioners' sugar and beat until light and fluffy.