In a large bowl, whisk together the yoghurt, mango purée, crushed cardamom, and sugar until smooth and well combined.
For best results, churn the Mango and Cardamom Frozen Yoghurt mixture in an ice cream maker according to the manufacturer’s instructions until it reaches a soft, scoopable consistency.
For a firmer texture, transfer to a freezer-safe container and freeze for an additional 1–2 hours.
Without an ice cream maker: freeze the mixture for 1½ hours, then stir with a fork to break up ice crystals. Repeat this process 2–3 times before freezing completely.
Before serving, let it sit at room temperature for 10–12 minutes to soften slightly.