1. Beat the egg whites until stiff and set aside.
2. In a bowl, mix flour and baking powder. Add egg yolks and mix with a whisk. Add milk and mix. Gently incorporate the beaten egg whites. Season with salt.
3. In a non-stick pan, heat 1 tablespoon of oil. Add small piles of dough. Cook blinis over low heat for 45 seconds on each side or until they slide in the pan. Transfer to a grill and let cool.
4. Slice the mozzarella balls using an egg slicer and set aside.
5. Cut small triangles from the grapefruit suprêmes; set aside.
6. Place a little pesto on each blini. Top with 2 mozzarella slices.
7. Add the grapefruit triangle and a pine nut for decoration.
8. Sprinkle with black salt and serve.