In a medium saucepan, combine 2 cups of water, 1 cup of white sugar, the juice from 1 large lime, 1 teaspoon of rum extract, and 1 teaspoon of citric acid powder. Stir well to combine thoroughly.

Place the saucepan over medium heat and bring it to a gentle boil while stirring until the sugar is fully dissolved, about 5 minutes. Remove from heat and let cool.

Transfer the mixture to a heatproof container and chill in the refrigerator for at least 1 hour until it cools down to around 40°F (4°C).

Pour the chilled mixture into your ice cream maker and churn according to the manufacturer's instructions for about 20-25 minutes until it reaches a soft-serve consistency.

Transfer the Daiquiri Ice to a tub or loaf pan, smooth the top, cover tightly, and freeze for at least 2 hours to firm up completely.