Install a rack in the middle of the oven. Then preheat to 350 degrees Fahrenheit. Then line a loaf pan with parchment, leaving an overhang on the long sides. Coat with nonstick spray. Toast shredded coconut on a baking sheet, occasionally tossing, until lightly browned, 5–7 minutes. Let cool.
Whisk rice flour, baking flour, tapioca starch, baking powder, baking soda, salt, and xanthan gum in a medium bowl. Set aside. Then combine sugar, coconut milk, and oil in a large bowl. Beat mixture with an electric mixture on medium speed until sugar dissolve (about 4 minutes). Add the eggs, one at a time. And Beat well after each addition. Beat the mixture well for another 2 minutes. Next, reduce the mixer speed to low. Then add your dry ingredients to the mix. Increase mixer speed back to medium and beat the mixture for about 5 minutes. Next, you will incorporate the toasted coconut. Beat well. Once beating completes, scrape the batter into a prepared pan, and sprinkle with coconut flakes.
Bake bread until top springs back, or when a tester inserted in the center comes a few crumbs attached, (80–90 minutes max). Transfer dough from oven to a wire rack, and let the bread cool in the pan for 10 minutes. Turn out dough onto a cooling rack and let cool completely.