In a medium saucepan, combine 2 cups of frozen blueberries, 2 cups of water, 1/4 cup of organic raw sugar, and 1 tablespoon of fresh lemon juice. Bring to a vigorous boil, then reduce heat and simmer for 5 minutes.

Use a potato masher or immersion blender to crush the blueberries, then pour through a fine sieve into a bowl to extract the juice. Set aside to cool.

In a separate large pot, bring 6 cups of water to a boil for the green tea. Remove from heat, add tea bags or loose leaves, and steep for 3 minutes. Strain into a pitcher and let cool.

Mix the cooled blueberry juice and remaining 1/4 cup of fresh lemon juice into the pitcher with green tea. Stir gently to combine.

Fill glasses with ice and pour the blueberry-lemon iced green tea over. Garnish with lemon slices or fresh mint leaves, and serve.