1. Preheat the oven to 450°. In a large bowl, toss the cauliflower with the oil, ginger and coriander and season with salt. Spread the cauliflower on a rimmed baking sheet and roast for about 40 minutes, stirring once or twice, until tender and lightly browned in spots. Let cool slightly.
2. Transfer the cauliflower to a food processor. Add the tahini and lemon juice and pulse to a chunky puree; season with salt. Add the cilantro and pulse just until incorporated. Transfer the spread to a bowl and sprinkle with sesame seeds. Serve warm with pita bread or chips.