Begin by filling a half-gallon (2-quart) pitcher halfway with crushed ice, then layer the thinly sliced lemons over the ice for a refreshing, citrusy aroma.
In a medium mixing bowl, whisk together the freshly squeezed lemon juice, granulated sugar, and sweetened condensed milk. Stir until the sugar is completely dissolved and the mixture becomes smooth and creamy. Adjust the sweetness by adding a little more condensed milk if desired.
Pour this lemon mixture into the prepared pitcher over the ice and lemon slices. Fill the remaining space with cold water, stirring gently to combine all the ingredients evenly.
Serve immediately over additional crushed ice for a chilled, velvety lemonade that’s both tangy and luxuriously smooth. Each sip delivers a balance of bright citrus flavor and creamy sweetness—perfect for sunny days or casual gatherings.