In a medium saucepan, bring 4 cups of water to a boil.

Once boiling, remove from heat and add the black tea bags. Steep for 5-7 minutes, depending on your desired strength.

While the tea is steeping, place the sliced strawberries in a blender. Blend until smooth.

After steeping, remove the tea bags and stir in the granulated sugar until dissolved.

Combine the strawberry puree with the sweetened tea in a large pitcher. Add the vanilla extract if using. Stir well.

Chill the mixture in the refrigerator for at least 1 hour.

To serve, fill glasses with ice cubes and pour the chilled strawberry iced tea over the ice. Garnish with fresh mint leaves if desired.