In a your soup pan, heat a few tablespoons of the olive oil up and add the garlic and shallots and sauté until the shallots are soft.
Add the carrots and sauté for about two minutes.
Add the potatoes and rosemary to the pot and stir to combine.
Add the remaining olive oil and cook for about 5 minutes. Stir the porcini along with the broth and salt.
Bring to a simmer and cook for 20 minutes, or until the potatoes are tender.
Once the potatoes are tender, taste. Adjust the salt, if you do not have enough salt the mushroom flavor will not be intense and if the broth is too intense, you can add more water a little bit at a time.