For the vanilla bean cookie dough - Cream together the butter, sugar, and vanilla bean until light and fluffy (about 5-7 minutes).
Combine cornstarch and water and add to the butter mixture. Mix well.
Sift together the flour and baking powder, then add to the butter mixture. Mix until the dough comes together in big chunks, then wrap in plastic and chill for 30 minutes.
For the chocolate cookie dough - Cream together the butter and sugar until light and fluffy (about 5-7 minutes).
Sift together the flour, cocoa powder, baking powder, and salt and add to the butter mixture. Mix well, then add the orange juice and mix until creamy (about 1 minute). Wrap in plastic and chill for 30 minutes.
Preheat the oven to 350ºF.
Unwrap both cookie doughs. Break the cookie doughs into chunks, then reassemble the doughs together alternating chocolate and vanilla.
On a lightly floured surface, roll the cookie dough out to about 1/2" thick, then use a heart-shaped cookie cutter to cut out the cookies. Continue patting the dough back together, rolling out, and cutting out cookies until all the dough is used up. Arrange on a parchment-lined baking sheet and place in the freezer for 10 minutes.
Bake 13-15 minutes until the cookies are set and lightly browned along the edges.