Start by infusing the oil. In a small pot, add the extra virgin olive oil, sage, thyme, and garlic. Set the heat to low and let it simmer for about 20 to 30 minutes.
In the meantime, peel the potatoes, cut them into small cubes, and add them to a pot of water with a pinch of salt, bring it to a boil. Cook then until nearly soft (5 min) before removing from the water and setting aside.
Thinly chop the shallots, carrot, and celery. Chop the sun-dried tomatoes into small pieces. Brush the mushrooms to make sure there’s no dirt left on them. Break them apart in irregular pieces using your hands. Chop the kale into thin and short strips.
Once the oil is ready, let it cool off for a few minutes and set two tablespoons aside. Put the rest in a big wide pan and set the stove to medium.
Once the oil is hot, add the celery and carrot. Fry while stirring often for about 3 minutes, then add the shallots and coriander seeds. When the shallots are translucent and the carrot and celery are soft, add the mushrooms and the oregano.
Mix it well adding the balsamic vinegar and turn the heat up to medium/high until the vinegar smell evaporates, then turn the stove down to medium again.
Add the potatoes, sun-dried tomatoes and kale along with a cup of water to the mixture and cook together for a further 10 minutes or until the potatoes are cooked through and all the liquid has evaporated.
Once the filling is ready, set it aside to cool down and get to work on the dough.