Heat oven to 350℉/177℃.
Line 2 sheet pans with parchment paper. Set aside.
In a small bowl, stir together cocoa powder and boiling water. Set aside
In a medium bowl, whisk together flour, almond flour, and baking powder. Set aside.
With an electric mixer, beat butter and sugar until light and fluffy, about 2-3 minutes.
Add egg, chocolate mixture, and vanilla.
Mix well.
Stir in flour mixture.
Turn out onto lightly floured parchment paper.
Roll to ¼" thick.
Cut out using desired cutters.
Place cookies on prepared pans.
Cut centers out of half the cookies.
Bake for 8-10 minutes, until firm.
When cookies have cooled, spread bottom halves with jam.
Top with matching cut-out cookie.
Dust with powdered sugar.