Combine the granulated sugar, 1 cup of water, and the sliced jalapeno peppers in a saucepan.

Bring the mixture to a simmer over medium heat, stirring occasionally until the sugar has completely dissolved.

Let it simmer for an additional 5 minutes to infuse the syrup with jalapeno flavor then let it cool.

Strain the cooled jalapeno syrup to remove the jalapeno slices.

Juice the lemons to get approximately 1 cup of lemon juice.

In a pitcher, combine the lemon juice, 4 cups of water, and the 1/2 cup of cooled jalapeno syrup. Stir well to mix the ingredients thoroughly.

Taste the jalapeno lemonade and adjust the sweetness and spiciness to your liking.

Place the pitcher in the refrigerator to chill for at least 1 hour, allowing the flavors to blend together.

Before serving, fill glasses with ice cubes. Give the jalapeno lemonade a good stir and pour it over the ice.