Combine: Add yogurt, nondairy milk, garlic, mint, cilantro, and lemon juice to a blender or small food processor.
Blend until smooth, adding water, olive oil, or more nondairy milk, one tablespoon at a time, until just pourable.
Taste and adjust seasoning. (See recipe notes.)
Notes
No blender? Chop the herbs and garlic finely, and whisk by hand.Seasonings (optional): Start with a pinch of turmeric, ¼ teaspoon each cumin and coriander, and a pinch of Kashmiri chili powder for balanced flavor and color—adjust to taste.Chill 10 minutes to let the flavors develop (optional but recommended).