Preheat the oven to 350°F. Line a baking sheet with parchment paper.
Sift the flours and starch into a medium bowl. Add oil and water and mix with your hands just until the dough forms. Season with salt and rosemary.
Place the dough on floured parchment or waxed paper. Roll out to ¼-inch thick, flouring the dough as needed. Cut out small squares (around 2 inches), and transfer to the baking sheet. Bake for 15 minutes, until golden brown. Let cool completely on a wire rack.
When ready to serve, spread 1 teaspoon cream cheese on each shortbread and season with salt and pepper. Top with smoked salmon and garnish with mint leaves.