Preheat oven to 375 degrees F; spray muffin tins with non-stick cooking spray or line with paper liners.
Prepare filling by mixing cream cheese, sugar, egg and lime juice in a large bowl with an electric mixer; mix well until smooth and set aside.
Prepare muffin mix by whisking flour, baking powder, salt and sugar in a large bowl and set aside.
In a medium bowl, mix syrup, margarine, eggs, milk and vanilla; beat until well.
Slowly mix the egg mixture with the flour mixture and blend until well combined.
Fold blueberries into batter, just enough so swirls appear.
Fill muffin tins 1/3 full with batter; add 1 tablespoon of cream cheese mixture and then another tablespoon of batter, or more to cover the cream cheese mixture.
Sprinkle a small amount of turbinado sugar (sugar in the raw) on top of each muffin and bake for 25 minutes.