The secret to the success of this recipe is to sofreir, a Spanish technique which involves cooking over low heat, frying slowly without browning.
Letting the potatoes steep in salt and spices before cooking releases water, allowing them to steam slowly in their own juices.
Peel and cut potatoes into 6 wedges. Place in a bowl; mix with salt and spices. Set aside.
Heat a heavy pan on medium heat. Pour in oil, add onions and cook slowly, stirring occasionally. Adjust heat as needed, stir-frying slowly without coloring the onions.
When onions become translucent (10-15 minutes), add potatoes, garlic and thyme. Mix well and cover.
Lower the heat once steam escapes from the cover. Carefully stir occasionally to prevent the potatoes from sticking. Cook until the potatoes begin to fall apart (25-30 minutes). Garnish with fresh herbs and serve.