Red Lentil Miso and Shiitake Mushroom Soup

Name: Red Lentil, Miso and Shiitake Mushroom Soup
Ingredients: 1/2 cup red lentils; 2 tablespoons extra-virgin olive oil; 1 large shallot, thinly sliced; 2 cloves garlic, minced; 1-inch knob fresh ginger, grated; 1/2 pound shiitake mushrooms, sliced; 6 cups vegetable stock; 3 tablespoons miso paste; Kosher or sea salt, to taste; Sliced green onions, for garnish