Leek & Mushroom Stuffing Soup

Ingredients 3/4 pound of button mushrooms or any mushroom of choice 1/2 pound of celery 1 1/2 pounds of leeks green tops removed 1 pound of fennel fronds and stalks removed 1/3 cup fresh rosemary 1/4 cup fresh sage leaves 3 garlic cloves 1/4 cup salted butter 1/4 cup extra-virgin olive oil 1/4 cup all-purpose flour Diamond Crystal kosher salt Freshly ground black pepper 1 teaspoon smoked paprika 1/2 teaspoon red pepper flakes 8 cups water 2 tablespoons Better Than Bouillon vegetable base 2 14-ounce cans of white beans 1/3 cup heavy cream 1/3 cup fresh parsley 1/4 cup fresh oregano 1 lemon for juicing Optional, for serving 6 large slices of sourdough bread torn