Preheat the oven to 400°F. Lightly grease the cups of a standard muffin pan or line with paper baking cups, and grease the paper cups.
Whisk together all the dry ingredients.
Then add in the vanilla extract, vegetable oil, and heavy cream. Then stir to combine.
Add in Blueberry's and fold into the batter.
Spoon the batter into the prepared muffin cups, filling them full. A slightly heaped spoonful of the batter is the right amount.
Sprinkle the tops of the muffins with coarse sparkling sugar or cinnamon sugar, if desired.
Bake the muffins for 18 to 20 minutes, until a toothpick inserted into the middle of one of the center muffins comes out clean.
Remove the muffins from the oven, and after 5 minutes (or when they're cool enough to handle) transfer them to a rack to cool.
Serve warm, or at room temperature. Store leftovers loosely wrapped at room temperature for several days; freeze for longer storage.