Start by making the syrup. Combine all the syrup ingredients in a pot and bring to a boil. Once it boils, remove from heat and set aside.

In a large bowl, mix the olive oil, sunflower oil, and sugar together well. Add the cinnamon, cloves, and orange zest, and mix again.

In a separate bowl, combine the orange juice and baking soda. It will foam up a lot. Pour this mixture into the oil mixture and stir. Once the foam settles a bit, add the walnuts, then gradually add the flour and baking powder, mixing slowly until you have a soft, pliable dough.

Shape the dough into oval cookies (melomakarona) and place them on a baking sheet, leaving some space between them as they will expand. Bake at 350°F (180°C) with the oven set to convection (fan) for about 7-13 minutes, depending on your oven. After baking, dip the cookies in the syrup, count to 10, then remove and sprinkle the extra grated walnuts on top.