Preheat oven to 350ºF. Line an 8 or 9 inch square pan with parchment paper. Grease it and set it aside.
In a bowl, mix together Mochiko rice flour, baking powder and salt.
Sift in the matcha into the flour mixture making sure there are no clumps. Mix until fully combined.
In another bowl, mix together butter, sugar, eggs, milk and vanilla until fully combined.
Pour the wet mixture into the dry mixture and mix until smooth.
Pour the batter into your lined and greased pan. Bake for 40 to 50 minutes or until the top browns slightly throughout. Set aside and let it cool.
In a separate bowl, pour in the white chocolate chips. Heat up the heavy cream until steaming but not boiling.
Pour hot heavy cream over chocolate chips. Let them sit for a minute to melt then mix until fully combined and smooth.
After mochi has cooled completely, spread ganache over bars. Cut them in squares and enjoy.
