Sobaos, spanish butter cake

I had to nearly execute an scientific research to find this sobaos* recipe. I've got one but, frankly, they came out like bricks. My kids allow me almost everything in the kitchen and they ate them with enthusiasm, but I wasn't satisfied.

First, I went to the supermarket and read the ingredients' percentages of our favorite sobaos brand. Then, I did several easy mathematical operations to adapt the recipe to these percentages. After a few attempts, two to be completley honest, the third time was the good one.

I'd like to share this recipe, so you all can enjoy them. I hope you like them as much as my kids do.

*This cakes come from Santander, north of Spain. We eat them at breakfast and as a snack.

Sobaos pasiegos

Ingredients:
400 gr. butter, room temperature350 gr. sugar300 flour5 eggs8 gr. baking powder
Method:
Beat butter and sugar until it turns whitish.Add eggs one at a time: first one, beat until fully incorporated, then another and so on till you've mixed them all.
Mix flour and baking powder and add it to the butter mixture with a wooden spoon. Stir just enough, if you overstir, cake will harden.Turn oven on at 180º C.Line an oven sheet with parment paper. Pour dough in, even out and bake for 20 minutes.Let cool on the sheet. Cut the cake in bars. I find they are even better after resting the night.
You can enjoy them for breakfast, coffee break, afterschool snack or during the day.