Boil Water: Heat 4 cups of water in a medium saucepan over high heat until boiling, about 8-10 minutes.

Brew Tea: Remove from heat and add black tea bags. Steep for 5-7 minutes to desired strength.

Prepare Blackberries: Mash 1 cup of blackberries in a bowl until juicy but textured.

Combine Ingredients: In a pitcher, strain the brewed tea, then add mashed blackberries, ½ cup lemon juice, and sweetener. Stir until dissolved.

Chill Mixture: Let cool at room temperature for 15-20 minutes, then refrigerate for 1-2 hours until cold.

Serve: Fill tall glasses with ice and pour the chilled tea over. Serve generously.

Garnish: Add lemon slices and mint leaves to each glass before serving.