Step 1: Preheat and Prep
Let’s dive in—crank your oven to 350°F and feel the kitchen hum with promise. Grab three 8-inch cake pans—spray them with non-stick baking spray and line the bottoms with parchment (I love that extra slip!). Take a sec to breathe—this is gonna be a peanut butter-chocolate wonder, and you’re already on your way.

Step 2: Whisk the Dry Mix
In a big mixer bowl, whisk 1 3/4 cups all-purpose flour, 2 cups sugar, 3/4 cup cocoa powder, 2 1/4 tsp baking soda, 1/2 tsp baking powder, and 1 tsp salt—give it a good stir (I love that cocoa cloud poofing up!). It’s all dry and ready—set it aside and feel the chocolate vibes starting. This is the base of our fudgy dream!

Step 3: Blend the Wet Magic
In a medium bowl, mix 1 cup milk, 1/2 cup vegetable oil, 1 1/2 tsp vanilla extract, and 2 large eggs—whisk ‘til smooth (I grin every time it blends!). Heat 1 cup water ‘til hot, add it in, and mix ‘til it’s a velvety batter—don’t worry about the thin look (my heart’s racing with that hot water trick!). This is where the moistness comes alive!

Step 4: Combine and Bake
Pour your wet mix into the dry—beat ‘til just combined, scraping the sides to catch every bit (I love seeing it turn fudgy!). Divide evenly between your three pans—smooth the tops and bake for 22-25 minutes—check with a toothpick ‘til it’s got a few crumbs (I watch them puff up with glee!). Cool in the pans for 2-3 minutes, then turn onto racks—I’m drooling already!

Step 5: Whip the Peanut Butter Frosting
In a big bowl, beat 2 cups salted butter and 1 1/4 cups peanut butter ‘til creamy—take your time (I love that nutty swirl!). Add 4 1/2 cups powdered sugar, mix ‘til smooth, then 3 tbsp water or milk—add the rest of the 4 1/2 cups sugar and 3-4 tbsp more liquid ‘til silky (I sneak a taste of that peanut bliss!). Keep it thick but spreadable—set aside this frosting heaven!

Step 6: Level and Stack
Grab a serrated knife—slice off the cake domes for flat layers (I nibble the scraps, don’t judge!). Place one layer on a plate—spread 1 cup frosting, sprinkle half of 6 chopped Reese’s, press them in, and add a thin frosting layer (I feel like a stacking pro!). Add the second layer, repeat with frosting and the rest of the chopped Reese’s—top with the third layer (I’m grinning at this tower!).

Step 7: Frost the Cake
Spread a thin crumb coat over the cake—seal those crumbs like spackle (I love this messy step!). Add 1 cup frosting to the top, smooth it out, then frost the sides—use an offset spatula to make stripes (I feel artsy swirling it!). This is where it turns into a peanut butter beauty.

Step 8: Make the Ganache
Toss 6 oz semi-sweet chocolate chips in a bowl—heat 1/2 cup heavy whipping cream ‘til it simmers, pour over the chips, and let sit 2-3 minutes (I love that steamy wait!). Whisk ‘til smooth—let it cool ‘til thick but pourable (I test it later—it’s drip time!).

Step 9: Drip and Decorate
Drizzle ganache around the edges with a spoon or bottle—fill the top and smooth with an offset spatula (I go slow and feel fancy!). Let it firm up 10 minutes—pipe swirls with leftover frosting using a star tip (I use Ateco 844—Wilton 2D works too!), then top with 8 halved Reese’s and crumbled Reese’s (I sprinkle like it’s a party!). This is the grand finale!

Step 10: Chill and Serve
Pop it in the fridge ‘til ready—serve at room temp for that fudgy bite (that first slice makes me sigh!). Pair it with milk or dig in—it’s peanut butter-chocolate joy, and you made it happen (store covered for 3-4 days—I sneak bites ‘til it’s gone!).