1Heat the oil in a deep, heavy saucepan over medium-high heat. Add the garlic, cumin, and turmeric and cook until fragrant, about 30 seconds. Add the onions, carrots, celery, and turnip if you’re using it and cook, stirring occasionally, until the vegetables begin to soften, about 10 minutes. Add the stock, bring to a boil, then lower the heat and simmer for 15 minutes.
2Stir in the curry powder and cool the mixture slightly if time allows (it’s never a good idea to puree boiling hot mixtures if you can avoid it). Use a food mill, an immersion blender, or an upright blender to puree the stew.
3Reheat the stew in the saucepan, season with salt and pepper, garnish with cilantro, and serve.