Grate the garlic first and set aside so it can sit for 10 minutes before using to get more health benefits.*
Wash, peel and dice the potatoes into ½in cubes. Place in a bowl of filtered water and set aside. The water will prevent the potatoes from turning color.
Heat a 5qt or larger pot to medium. Add the cumin and coriander seeds and heat through until fragrant (about 1 minute). Pour the spices into a bowl to allow to cool, then place in a spice bag. Set aside.
Lower the heat to medium low and remove the pan from the burner for a couple minutes to make sure the pan isn’t so hot it will burn the garlic (add a tiny amount of garlic to check).Return the pan to the burner and add the grated garlic to the pan. Push the garlic down with the flat edge of the spatula to form a thin layer on the bottom of the pan.Heat through until most of the grated garlic sticks to the pan surface and becomes a light golden color. Don’t allow to become browned, this will make the garlic bitter and will give an off taste in this delicate soup.
In a dry section of the pan, add the saffron and toast a few seconds.
Add 2–3 Tbls of garlic stock to deglaze (release the garlic from the pan) and continue to sautée a minute or two longer.
Add the miso and stir with the garlic.
Drain the diced potatoes, then add to the pan. Stir to coat with garlic mixture. Cook a few minutes more to develop the flavor.
Add the garlic stock (preferably hot) 1 cup at a time, stirring after each cup. Once all the stock is in, add the spice bag.
Simmer on medium heat 20 minutes or more until the potatoes are done.
Garnish with fresh cut herbs and/or toast with pesto. A squeeze of lemon juice will brighten the soup.