01 - Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners.
02 - In a medium bowl, whisk together all-purpose flour, baking powder, baking soda, and salt. Set aside.
03 - In a large bowl, beat cream cheese, butter, and granulated sugar until light and fluffy, about 2 to 3 minutes.
04 - Add eggs one at a time, beating thoroughly after each addition. Mix in vanilla extract and lemon zest if using.
05 - Combine whole milk and cooled sweet tea in a small bowl.
06 - Add the dry ingredient mixture to the wet ingredients in three parts, alternating with the milk-tea blend, starting and ending with dry ingredients. Mix just until combined; avoid over-mixing.
07 - Divide the batter evenly among muffin cups, filling each approximately two-thirds full.
08 - Bake muffins for 20 to 22 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
09 - Allow muffins to cool in the pan for 5 minutes, then transfer to a wire rack to cool completely before serving.