Preheat oven to 400F. Line a muffin tin with 12 paper baking cups. Set aside.
To make cream cheese mixture, mix together cream cheese, sugar, and vanilla with a hand mixer until creamy. Set aside.
Set aside 1 tablespoon of the gluten-free flour blend to toss with the blueberries later.
In another bowl, whisk together the remaining gluten-free flour blend, xanthan gum (if your flour blend does not already contain it, baking powder, baking soda, ground cinnamon and salt. Set aside.
In a large bowl, cream together granulated sugar and vegetable oil for 2 minutes.
Then, add the eggs to the sugar mixture and beat until combined and smooth, about 1-2 minutes.
Pour the vanilla and milk into the mixture and mix well until combined.
Then, gradually add the flour mixture to the wet ingredients, mixing until just combined.
Toss the blueberries with the 1 tablespoon of gluten-free flour until they are coated. This will help them from sinking to the bottom of the muffins.
Then, add 1 cup of the blueberries to the muffin batter and stir carefully until combined, being careful not to break any blueberries open.
Fill each cup 3/4 full with the muffin batter. Top the batter with remaining 1/4 cup of blueberries.
Then, spoon about a heaping teaspoon full of cream cheese mixture on top of each muffin well. Sprinkle with turbinado sugar.
Bake at 400F for 16-18 minutes, until the muffins are lightly browned and an inserted toothpick comes out clean. Let cool in the pan for 5 minutes before removing to a wire rack to finish cooling.