Another great recipe from here (link in Hebrew). I made it yesterday and it looks like it will be gone before Shabbat. The most deliciously soft, moist and simple chocolate cake I've ever tasted.
1 cup sugar (it says 2 cups in the original recipe, but I knew it would be too sweet for us. 1 cup is plenty).
1 cup cocoa powder (my husband said it's a tiny bit too much - I might make 3/4 cup next time)
1 cup all-purpose flour
1 tbsp. baking powder
1 cup (100 gr) grated coconut
1\2 cup oil (it says 1 cup in the recipe, but again, I know my husband likes less oil, and it turned out great)
Mix well. Add 2 cups water and mix again. The mixture is supposed to be runny - you may add a tiny bit of flour and not more.
Pour into baking tray and bake until knife comes out clean. I'm not sure about the temperature because each oven is different, I usually bake at a temperature much lower than stated in the original recipes if I don't want to burn whatever I'm making.
I just enjoyed a slice of this cake now and must resist the temptation of taking another one!