Preheat the oven to 350F (175C). Line an 8×8 baking pan with parchment paper (or grease with oil or butter)
In a large bowl, combine glutinous rice flour, matcha, baking powder, and salt. Whisk well.
In a separate bowl, combine eggs and sugar. Whisk well until combined. Add the butter, milk, and vanilla extract and mix well.
Pour the wet ingredients into the dry ingredients and mix until fully incorporated.
Pour the batter into the prepared baking pan and bake in the middle rack of the oven for 60 minutes or until a toothpick inserted comes out clean.
Remove the butter mochi from the oven and allow to cool for 15 minutes. Slice and enjoy while fresh!
