01 - Preheat oven to 350°F (175°C). Line a 12-cup muffin tin with paper liners or lightly grease the cups.
02 - In a large bowl, whisk together sweet rice flour, granulated sugar, baking powder, and salt until well blended.
03 - In a separate bowl, whisk together whole milk, eggs, melted butter, ube halaya or puree, and vanilla extract until smooth.
04 - Pour the wet mixture into the dry ingredients and mix until just incorporated, avoiding overmixing.
05 - Gently fold in dried cranberries, ensuring even distribution throughout the batter.
06 - Divide the batter evenly among muffin tin cups, filling each about three-quarters full. Sprinkle coconut flakes on top if desired.
07 - Bake for 32 to 36 minutes, or until the muffins are set and the tops spring back when pressed gently.
08 - Allow muffins to cool in the pan for 10 minutes. Transfer to a wire rack and let cool completely before serving.