Preheat oven to 338°F (170 °C). Prepare a flat tray, covered with baking paper.
Put the butter and sugar in the mixer bowl, beat. Scrape off the bottom with a spatula. Pour in the oil in a thin trickle while beating nonstop on low until homogeneous. Add the vanilla and coconut flakes, beat on low until the products mix together.
Add the flour in portions, beat just enough for it to get absorbed. Take it out of the mixer bowl, put in foil and leave in the fridge for at least 2 hours. After that, take it out and tear off balls (1 oz (30 g) each), shape them between your palms and arrange in the baking tray.
Bake at 338°F (170 °C) about 10-15 min. max. The sweets need to remain white and not bake too long because they'll crack.
Take them out of the oven and leave about 5-7 min. in the same tray because they're extremely delicate and break. After cooling but while still warm, first roll them in coconut flakes, then in powdered sugar. Arrange nicely and serve.
Source: Savinch Adil
Notes: Some clarifications: about 1 2/3 cups (400 g) is what you'll need for a soft dough. When you squeeze the dough in your hand it needs to leave finger marks behind.
It's an extremely crumbly dough but after you put it away in foil and let it it cool it tightens very well. Tear balls, form them between your fingers - the dough will relax and be malleable.
Bake for 15 min. max. Keen an eye on them because they burn quick, get cracks and fall apart. They need to remain pure white.