Combine flour & sugar & baking powder & salt. Beat eggs,milk & oil. Stir into dry ingredients. Fold in blueberries.
Transfer to a greased & floured 13*9 pan. Bake at 375 for 30 to 35 mins. NOTE (12 way through baking sprinkle the cup of coconut over cake. Check w toothpick, when toothpick comes out clean, remove cake from oven cool on wire rack.
In a small saucepan comine sugar, cornstarch & lemon zest. Gradually add water until blended. Bring to a boil, cook & stir 2 mins or till thickened. Remove from heat add butter & fresh lemon juice. Cut cake into squares drizzle with lemon sauce.