Creating this incredible frozen citrus ‘soufflé’ is straightforward if you follow these easy steps:

1. Prepare the Citrus Juices: Squeeze the lemons, oranges, and limes to extract the fresh juice. Strain to remove seeds, then measure 1 cup each of lemon and orange juice and ½ cup of lime juice.

2. Zest the Lemons: Grate the outer layer of about 1-2 lemons to collect 1 tablespoon of lemon zest.

3. Mix the Sugar and Juices: In a mixing bowl, combine the fresh lemon juice, orange juice, lime juice, and granulated sugar. Stir until the sugar is completely dissolved.

4. Incorporate the Zest and Yogurt: Add the lemon zest and Greek yogurt to the juice mixture. Stir well until smooth and combined.

5. Whip the Cream: In a separate bowl, whip the heavy cream until soft peaks form. Gently fold this whipped cream into the citrus mixture, being careful not to deflate it.

6. Whip the Egg Whites: In a clean mixing bowl, beat the egg whites with a pinch of salt until stiff peaks form.

7. Combine Mixtures: Gently fold the whipped egg whites into the citrus mixture. Do this in stages—first folding a third of the egg whites in to lighten the mixture, then fold in the rest.

8. Prepare to Freeze: Pour the entire mixture into a freezer-safe container or a loaf pan. Smooth out the top with a spatula.

9. Freeze: Cover the container with plastic wrap or a lid and freeze for at least 3 hours or until thoroughly set.

10. Serve Cold: When ready to serve, remove from the freezer and let sit at room temperature for about 5 minutes. Scoop into bowls or dessert glasses.