In a 12-inch skillet set over medium heat, toast the cumin seeds, stirring often, until fragrant and slightly darker, 2 to 3 to minutes.
Transfer to a small bowl; set the skillet aside.
Using your hands, squeeze the shredded cucumber to remove excess water, then add to the bowl with the cumin, along with the yogurt, mint, and ¼ teaspoon salt, then stir to combine and set aside.
In the same skillet over medium-high heat, warm the ghee until barely smoking.
Add the cauliflower in an even layer and cook without stirring until well charred on the bottom, 4 to 5 minutes.
Stir in the chilies, turmeric, ½ teaspoon salt, and 3 tablespoons water, then immediately cover.
Reduce to low and cook, stirring once or twice, until the pan is dry and the cauliflower is tender, 15 to 17 minutes.
Taste and season with salt and pepper.
Transfer to a serving dish, sprinkle with the cashews, and serve with the raita.