Begin by peeling and chopping the ripe Bartlett pear into small chunks. In a blender, combine the chopped pear, freshly squeezed lemon juice, granulated sugar, and Thai basil leaves. Blend on high for about 30-40 seconds until smooth.

Prepare a fine-mesh sieve over a clean pitcher and pour the pear mixture into the sieve, pressing down on the solids to extract as much liquid as possible. Discard the solids left in the sieve.

Slowly mix in about 4 cups of cold water to the strained pear-basil liquid, stirring gently to combine.

Fill tall glasses with ice cubes and pour the refreshing lemonade over the ice, allowing the vibrant colors to shine through.

Garnish each glass with fresh basil sprigs before serving immediately.