Preheat the oven to 350 degrees F (177 degrees C).
Make your browned butter. Heat butter over medium heat until it fully melts. Lower the heat to low and cook until the butter is golden brown. Pour into a large mixing bowl and set aside to cool.
Add the coconut milk to a small bowl and heat coconut milk in the microwave for 30 seconds. Add the hojicha powder and stir until incorporated. Set aside.
Once the butter has cooled down, add the granulated sugar, vanilla extract, and eggs to the bowl. Mix until incorporated.
Add the hojicha coconut milk to the bowl and mix.
Finally, add the sweet rice flour and baking powder and mix until a smooth, thick mixture forms. The batter will be a bit lumpy, so make sure you use a whisk to mix. The whisk helps you get that smooth texture.
Grease a muffin pan. Scoop batter into the muffin pan. Smack the muffin pan 1-2 times on a flat surface to get rid of some of the air bubbles.
Bake for 30 minutes until the edges start to brown.
Cool for 10 minutes before serving.