Wash the lemons thoroughly.

Juice the lemons using a citrus juicer to get about one cup of lemon juice.

In a separate bowl, combine sugar with one cup of hot water and stir until sugar is completely dissolved to create a simple syrup.

In a pitcher, mix the freshly squeezed lemon juice with the simple syrup.

Add the remaining three cups of cold water and stir well.

Taste the lemonade and adjust the sweetness or tartness if needed.

Refrigerate the lemonade for at least 30 minutes.

Serve in glasses filled with ice and garnish with lemon slices and mint if desired.