Preheat the oven to 350°F. Lightly grease two 9" round cake pans., Whisk together the flour or flour blend, xanthan gum, and Cake Enhancer., In a separate bowl, use an electric mixer to beat together the sugar, soft butter, salt, baking powder, and vanilla for 45 seconds at medium-high speed, until smooth., Scrape the bottom and sides of the bowl. Still using the mixer, beat in the eggs one at a time; the mixture should become quite fluffy. Scrape the bottom and sides of the bowl again., Continuing to use the mixer, mix in the milk, at low speed, alternately with the dry ingredients, adding about 1/3 of each at a time, and ending with the dry ingredients. The batter will look curdled after the milk addition; that's OK, it will come back together once the final addition of flour has been mixed in for 30 to 45 seconds., Scoop the batter into the prepared pans. Bake the cake for about 25 to 30 minutes, about 3 to 4 minutes past the point where the cake springs back when touched lightly in the center, and a cake tester (or toothpick) inserted into the middle comes out clean. The finished cake's internal temperature should be 210°F., Remove from the oven, and cool for 5 to 10 minutes before turning out of the pan to cool on a rack.