Step 1: Preheat and Prep
Let’s get indulgent—crank your oven to 350°F (175°C) and feel the kitchen hum with promise. Grease two 9-inch round cake pans with butter, dust with flour, and line the bottoms with parchment (I love that extra slip!). Take a sec to breathe—this is gonna be a crunchy wonder, and you’re already on your way.

Step 2: Mix the Dry Goods
In a big bowl, whisk 2 1/2 cups all-purpose flour, 1 tsp baking powder, 1/2 tsp baking soda, and 1/2 tsp salt—give it a good stir (I love that floury puff!). This is the fluffy foundation—set it aside (my kitchen’s buzzing with anticipation!).

Step 3: Cream the Base
In another big bowl, beat 1 cup softened unsalted butter and 1 1/2 cups granulated sugar with a mixer ‘til light and fluffy—takes 3-4 minutes (I grin every time it fluffs up!). Add 4 large eggs one at a time—beat well after each, then stir in 1 tsp vanilla (my heart’s racing with buttery joy!). This is the sweet heart of our cake!

Step 4: Combine the Batter
Alternate adding the dry mix and 1 cup buttermilk to the butter mixture—start and end with dry, mixing ‘til just combined (I feel pro layering it in!). Scrape the bowl—don’t overmix (I’m gentle here—it’s all love!). Divide evenly between your two pans—smooth the tops with a spatula (I’m drooling already!).

Step 5: Bake the Layers
Bake for 25-30 minutes—check ‘til a toothpick’s clean (I watch with glee as they puff up golden!). Cool in pans 10 minutes—turn onto racks and let cool completely (that vanilla scent’s got me hooked!).

Step 6: Make the Caramel Sauce
In a medium saucepan, heat 1 cup granulated sugar over medium—stir constantly ‘til it melts and turns amber (I love that golden swirl!). Add 6 tbsp cubed unsalted butter—stir ‘til melted (it bubbles like crazy!). Slowly pour in 1/2 cup heavy cream—keep stirring, add a pinch of salt, and cook 1-2 minutes ‘til smooth (my kitchen smells like caramel heaven!). Cool slightly—set aside (I sneak a taste—it’s gooey bliss!).

Step 7: Whip the Frosting
Beat 1 1/2 cups softened unsalted butter ‘til creamy—gradually add 4 cups powdered sugar, 1/4 cup caramel sauce, and 1 tsp vanilla (I love that silky start!). Add 2 tbsp heavy cream—beat ‘til fluffy and spreadable (I swirl it with glee!). Adjust with more cream if needed—it’s frosting time!

Step 8: Assemble and Decorate
Place one cooled layer on a stand—spread frosting, drizzle caramel, sprinkle 1 cup crushed toffee pieces (I feel like a candy artist!). Stack the second layer—frost the top and sides (I go wild with swirls!). Top with more toffee, 1/4 cup chopped pecans if using, and drizzle with caramel—slice and serve (that first bite’s pure crunch bliss, and you made it happen!). Store covered—I sneak bites ‘til it’s gone!