Nonstick cooking spray
1 15-ounce container coconut pecan frosting
4 large eggs
3/4 cup vegetable oil
1 cup water
1 15 1/4-ounce box butter pecan cake mix
1 cup pecans, toasted and chopped, divided
1 14-ounce can sweetened condensed milk
2 tablespoons unsalted butter
Heat the oven to 350 F and spray a 9-by-13-inch baking dish with nonstick cooking spray.
In a large mixing bowl, combine the frosting, eggs and oil, and whisk together.
Add the water and mix to combine.
Add half the cake mix, and whisk it in before adding the second half of the cake mix and mixing well.
Stir in 1/2 cup of the pecans.
Transfer the batter to the prepared baking dish.
Bake for 40 minutes, until the top is golden brown and the cake pulls away from the sides.
Remove the pan from the oven, and let it cool on a wire rack.
While the cake is cooling, make the topping. In a small saucepan over medium heat, melt the butter and stir it together with the sweetened condensed milk.
Add the remaining 1/2 cup of pecans, and stir to combine.
Once the cake has cooled, pour the topping over the top.
Serve at room temperature.