Spray a Pyrex 9" x 13" x 2” baking dish with baker spray and set aside.
In large mix bowl combine milk, eggs, vanilla extract and butter and combine together with an electric mixer. Add in the sugar and mix well than add rice flour and baking powder when the mixture is combining add in the coconut and mix together and pour into the baking pan and into the oven for 1 hour.
After baking remove from oven and place onto a rack and with a knife run along the edge of the mochi to release from the side of the pan. Cool the mochi to down to room temperature before slicing.