Carefully prepare the prickly pears: wearing gloves or using tongs, remove the skin and thorns. Rinse the peeled fruit, then chop into roughly 1-inch pieces until you have about 4 cups of fruit.

Cook fruit

Place the chopped prickly pears in a medium saucepan with 1 cup water. Bring to a gentle simmer over medium heat, stirring occasionally, and cook for 8–10 minutes until the fruit is soft and broken down.

Blend and strain

Remove the pan from heat and let it cool slightly (2–3 minutes). Transfer the cooked fruit and liquid to a blender and puree until smooth (30–45 seconds). Strain the puree through a fine-mesh sieve or cheesecloth into a bowl or measuring cup, pressing with a spoon to extract as much juice as possible. Discard solids. You should have roughly 1 to 1 1/4 cups of prickly pear juice.

Make syrup

Return the strained prickly pear juice to the saucepan, add 1 cup granulated sugar and 1 tablespoon fresh lemon juice (optional, for brightness). Warm over low-medium heat, stirring until the sugar fully dissolves (about 3–5 minutes). Do not boil vigorously. Once dissolved and slightly thickened, remove from heat and let cool to room temperature. This yields about 1 cup syrup.

Chill syrup

Transfer the syrup to a jar, cover, and refrigerate for at least 30 minutes if using immediately. Syrup will keep in the refrigerator for up to 7 days.

Assemble Lemonade

Measure and combine: In a large pitcher, combine 1 cup fresh lemon juice and 1 cup prickly pear syrup.

Add water and taste: Stir in 4 cups cold water. Taste and adjust sweetness or tartness — add more water to dilute, more syrup to sweeten, or an extra tablespoon of lemon juice if it needs more brightness.

Serve: Fill glasses with ice (about 1/2 cup to 1 cup ice per glass). Pour lemonade over ice, gently stirring the pitcher before pouring to ensure syrup is distributed.

Garnish and finish: Garnish each glass with a lemon slice and a mint sprig if desired. Serve immediately.