Soak the chickpeas from the previous morning in water with coarse salt or baking soda. In the evening, wash them well, place them in a terracotta baking dish with a lid (preferably). Sink in the cloves of garlic. Place the onion slices on on top of the chickpeas and then add the tomato slices on top of those.

Add salt, pepper and the water, as much as is needed to cover the chickpeas. Then the oil and cover with the lid. Make a small piece of dough with water and flour and seal the terracotta baking dish thoroughly. Start a nice hot fire in the fireplace and once you have hot enough embers, place the terracotta dish in the middle and cover it well with embers all around its sides. Leave until morning.

In the morning, open the lid and if you see that it needs a little more cooking place it in the oven at 150°C until the chickpeas are cooked.