In a medium bowl, combine the flour, baking powder, salt, baking soda, ground cardamom, and half (3 Tablespoons) of the sesame seeds.
Place the 1/2 cup oil and the 1/2 cup granulated sugar in a large bowl and with an electric mixer on medium- high speed, beat until well blended, about one to two minutes. Add the eggs and beat another one to two minutes.
Move the mixer speed to low and add in the tangerine zest and juice. Then add the flour mixture and beat on medium-low speed until the batter is smooth, about 1 minute more. Scrape the batter into the prepared 8" pan. Set aside 1 teaspoon of sesame seeds. Sprinkle the remaining sesame seeds over batter.
Bake the cake until the top is golden and a toothpick inserted in center comes out clean, about 30 to 35 minutes. Let the cake cool on a rack 10 for minutes then loosen the cake from sides of pan and invert onto a cooling rack. Invert the cake, sesame-side up, onto another rack and let cool completely.