Preheat your oven to 350°F (175°C). Line a muffin tin with muffin liners or grease with non-stick spray.
In a large mixing bowl, combine the flour, sugar, baking powder, baking soda, salt, and cinnamon. Mix well.
In another bowl, whisk together the melted butter, eggs, vanilla extract, and buttermilk until smooth.
Pour the wet ingredients into the dry ingredients, gently mixing until just combined. Be careful not to overmix.
In a separate bowl, make the cheesecake filling by beating the softened cream cheese with the sugar, egg, and vanilla extract until smooth and creamy.
Fill each muffin cup about halfway with the muffin batter. Add a generous spoonful of cheesecake filling in the center of each muffin, and then top with a little more muffin batter to cover the filling.
In a small bowl, mix the granulated sugar and ground cinnamon for the topping. Sprinkle this mixture over each muffin.
Bake in the preheated oven for 18-20 minutes, or until a toothpick inserted into the muffin (not touching the cheesecake filling) comes out clean.
Allow the muffins to cool in the tin for 5 minutes before transferring them to a cooling rack.