additional ingredients called for on the box to make the cake (eggs, oil and water)
For the blueberry sauce:
1 ½cupblueberries,fresh or frozen
1large lemon,zest and juice
For the topping:
½cupjarred lemon curd
1(8 oz)container whipped topping (COOL WHIP)
Prepare the lemon cake according to the package directions for a 9x13 baking dish.
While cake is baking, prepare the blueberry lemon sauce. In a medium saucepan, add blueberries, lemon zest, lemon juice, sugar, cornstarch, and salt. Stir to combine. Cook over medium heat, stirring occasionally, until the mixture starts to bubble and thicken. Remove from heat and stir in the vanilla. Set aside.
Remove the cake from the oven and allow it to cool for 5 minutes. Use the handle of a wooden spoon to poke holes into the cake that are about an inch apart.
While the cake is still warm, drizzle the blueberry lemon sauce on top. Spread the sauce into an even layer over the cake ensuring some of the sauce and blueberries get down into the holes. Let the cake cool completely (about an hour.)
In a large bowl, whisk together the the lemon curd and the whipped topping until smooth. Spread the whipped lemon topping on top of the cake into an even layer. Place the cake in the refrigerator for at least 1 hour before serving.