Arrange the potatoes cut into slightly thin slices on a baking tray. Add the julienned onion on top and then the tomatoes, also cut into slices. Season with salt and pepper.
On top of the potatoes, we will put the thighs (or shoulder). We will have the oven preheated to 175º and we will introduce the tray inside for half an hour.
Meanwhile, we will have chopped the garlic in the mortar, with the parsley, rosemary and thyme (the herbs can be from spice jars). Add the oil and stir well.
After half an hour of cooking we will turn the pieces, we will pour the wine (or cava) on top and then the chopped herbs that we have made.
Half an hour later we will turn the meat again, which we will have been watering with the cooking juice.
After half an hour turn again. In total you should cook about 1 hour and a half.
It is a delicious dish and the meat is like cotton.
You try it and you will see that you will agree with me.