30 Minute Tuscan White Bean and Kale Soup

olive oil

medium sweet potatoes, cut into ½-inch pieces

medium onion

ribs celery

garlic

dried rosemary

dried thyme

salt

black pepper

each) cans cannellini beans, rinsed and drained

low sodium vegetable broth

medium bunch kale, removed from tough stems and chopped (about 4 packed cups)