1. Step 1: Prepare Your Chocolate Cake Layers.

2. Preheat oven to 350°F (175°C). Grease and flour two 8-inch or 9-inch round cake pans. Line bottoms with parchment paper.

3. In a large bowl, whisk together flour, granulated sugar, cocoa powder, baking soda, baking powder, and salt.

4. In a separate bowl, whisk eggs, milk, vegetable oil, and vanilla until combined.

5. Pour wet ingredients into dry; mix on low speed or by hand until just combined (do not overmix).

6. Carefully add boiling water; mix on low until smooth (batter will be thin).

7. Divide batter evenly between pans. Bake 30-35 minutes, until a skewer inserted in center comes out clean.

8. Cool in pans 10-15 minutes, then invert onto a wire rack to cool completely.

9. Step 2: Make the Homemade Caramel Sauce.

10. In a medium saucepan, combine 1 cup sugar and 1/4 cup water; stir gently to moisten. Cook over medium heat without stirring until sugar dissolves and mixture boils.

11. Continue cooking, swirling pan occasionally, until syrup turns rich amber (about 8-10 minutes). Watch carefully to avoid burning.

12. Remove from heat; carefully pour in warm cream (mixture will bubble vigorously). Whisk until smooth.

13. Add butter and salt; whisk until melted and glossy.

14. Pour caramel into a heatproof bowl; let cool completely at room temperature, stirring occasionally. It will thicken as it cools.

15. Step 3: Prepare the Pecan Topping and Frosting.

16. Spread chopped pecans on a baking sheet. Toast in preheated oven or dry skillet for 5-7 minutes until fragrant and lightly browned. Cool completely.

17. For frosting: In a medium bowl, beat softened butter until creamy. Gradually add powdered sugar, beating until smooth. Add milk/cream and vanilla; beat until light and fluffy. Adjust consistency with more milk or powdered sugar if needed.

18. Step 4: Assemble Your Chocolate Caramel Pecan Cake.

19. Level cake tops with a serrated knife if domed.

20. Place one cooled cake layer on serving plate.

21. Spread about half the cooled caramel evenly over top, leaving a small border.

22. Sprinkle about half the toasted pecans over caramel.

23. Place second cake layer on top.

24. Spread remaining caramel over top, leaving a small border. Sprinkle remaining pecans over caramel.

25. Apply powdered sugar frosting to sides of cake using an offset spatula (naked or fully covered as desired).

26. Chill cake in refrigerator for at least 30 minutes before slicing and serving.