Heat oven to 350°F.
Whisk the eggs, oil, and water together. Add the Chocolate Cake MIx and stir to combine. Don't overmix.
Pour into a greased 9x13 pan. Bake 24-30 min or until a toothpick inserted in center comes out clean. Remove cake from the oven and allow to cool slightly.
Using a straw, poke holes all over the top of the cake.
Transfer the dulce de leche to a microwave-safe bowl and warm in the microwave for 1 1/2 to 2 minutes, or until pourable. Pour the dulce de leche over the top of the cake and spread evenly, allowing the caramel to fill in the holes on the cake. Set the cake aside to cool completely.
Once the cake is completely cool, make the frosting: Place the softened butter in a mixing bowl. Add the Dark Chocolate Frosting Mix and blend at low speed until combined. Add the milk 1 tablespoon at a time, blending well after each addition.
Spread the chocolate frosting over the cooled cake. Drizzle with caramel syrup, then chocolate syrup, and top with pecan pieces. Serve immediately or store in the refrigerator until serving.