01 -  Preheat oven to 375°F. Line a 12-cup muffin tin with paper liners or grease lightly. 
 02 -  In a large mixing bowl, whisk together ricotta, eggs, milk, vegetable oil, vanilla extract, lemon zest, and lemon juice until smooth and well combined. 
 03 -  In a separate bowl, combine all-purpose flour, granulated sugar, baking powder, baking soda, and salt with a whisk. 
 04 -  Add the dry mixture to the wet ingredients. Stir gently using a spatula until just incorporated. Do not overmix; a few lumps remaining are acceptable. 
 05 -  Fold in the diced mango delicately to avoid crushing the fruit. 
 06 -  Evenly divide the batter among the prepared muffin cups, filling each about three-quarters full. 
 07 -  Place muffin tin in the oven and bake for 20 to 22 minutes, until the tops are golden and a toothpick inserted into the center emerges clean. 
 08 -  Allow muffins to cool in the pan for 5 minutes. Transfer them to a wire rack to cool completely before serving.