Mix the flour and baking powder.
Add the mahleb (or mahalepi), vinegar and vanilla and mix.
Add the baking powder and flour mixture and using the flat beater, mix until smooth. Do not knead too long.
Preheat oven to 320 F (160°C) and line two large baking sheets with parchment paper.
Place the cookies on the baking sheet with the sesame seed side up, spacing them approximately 1 inch (2,5 cm).