Brown lentils are the secret to keeping this hearty one-pot stew rich and filling without needing any advance soaking time. We'll start by sweating down our aromatic vegetables, then let them simmer alongside sweet potato, red potato, and the lentils until every bite is spoon-tender. Tossing the kale in toward the end gives it just enough time to soften up nicely without melting away completely into the liquid.

Using two kinds of potatoes really gives you the best of both worlds: the sweet potato breaks down slightly to enrich the broth, while the waxy red potato holds its own structure. If you find the lentils soak up extra moisture when reheating leftovers later, just loosen things up with a splash of water.