***I use 3 cups of cut up frozen mangoes from Trader Joes, defrost them in the microwave, and dice them.***.
Preheat Oven at 350* Grease square baking pan.
Combine Flour, Baking Soda, Baking Powder, Salt and Ginger. Add 1 c butter, mango & egg yolks & whip well.
Pour batter into pan and bake for 35-40 minutes. 5 minutes before done -- cut up 1/8 butter and place evenly over the top for a buttery crust. Done when you poke a knife in the middle and it comes out clean.