Preheat the oven to 190 degrees celsius.
Cut the apples in small cubes. Spinkel the cinnamon over the apples and stir so they get covered with cinnamon. Set aside.
Grease a 12-cup muffin pan or use muffin papers.
In a mixing bowl, put sugar butter salt, baking powder and vanilla. Beat it with a electir mixer until fluffy.
Beat in eggs, one at a time. Scrape the sides of the bowl so everything mixes properly.
Combine Flour mix and xanthan gum.
Fold in the flour mixture alternately with milk. First a little flour and then a little milk. Don't mix it too much so the volume goes away. You can use a spatula to fold in the flour and milk.
Fold in the apples or berries if you prefer that.
Scoop the batter into the prepared muffin pan.