Place the mushrooms in a bowl with 2 cups water; let them stand for about 15 minutes until tender.

Meanwhile, thinly slice the onions. Peel the carrots; chop the carrots and celery into bite-sized pieces. Mince the garlic and sage.

In a large pot or Dutch oven, heat the olive oil over medium heat. Add the onions and saute 3 to 4 minutes.

Remove the porcini mushrooms from the water and roughly chop them; save the water for adding to the soup. Add the mushrooms and saute for 5 minutes until onions are tender, making sure to stir often.

Add the celery and carrots and saute for 3 minutes. Add the garlic and sage and saute for 2 minutes.

Deglaze the pan with the apple cider vinegar and stir for a few seconds until evaporated.

Gently add the tomatoes and cook 2 for more minutes. Then add the broth, mushroom liquid, drained chickpeas and salt. Bring to a simmer and simmer for 10 minutes.

Add the spinach and stir for a few seconds until wilted.

Taste and adjust salt as necessary, then serve.