Heat 1 tablespoon oil in small skillet over medium heat until shimmering. Add shallot and cook until softened, about 2 minutes. Stir in garlic, cumin, and pepper flakes and cook until fragrant, about 30 seconds. Remove from heat and whisk in yogurt, water, lime juice, and remaining 1 tablespoon oil. Season with salt and pepper to taste and cover to keep warm. Stir in cilantro just before serving.

Makes about 1 cup