Mushroom and Wild Rice Slow-Cooker Stew

olive oil

cup(s) uncooked leek(s) finely chopped, white parts only (about 2 large leeks)

cup(s) dried shiitake mushroom(s) sliced

cup(s) uncooked carrot(s) diced

cup(s) vegetable broth

table salt

cup(s) uncooked wild rice