1. For the cream, chill the heavy cream in the refrigerator for at least 2 hours (or overnight). Also chill the mixing bowl and beaters. Whip the cream with a mixer on medium speed, gradually increasing it until thick peaks form.
2. Prepare the mango. Peel a ripe mango, slice off the pulp, and blend until smooth. If the mango is fibrous, pass the puree through a sieve.
3. Squeeze the juice from the lemon, ensuring no seeds get into the juice.
4. In a large bowl, combine the yogurt, mango puree, powdered sugar, and lemon juice. Mix until smooth.
5. Gently fold the whipped cream into the yogurt-mango mixture using a spatula with bottom-to-top movements to maintain lightness.
6. Pour the mixture into a container and place in the freezer. Every 40–50 minutes, mix thoroughly with a mixer or fork to break up ice crystals (repeat 4–5 times).
7. Serve in tall glasses, garnished with fresh mango slices or berries.