Step 1: Preheat and Prep
Let’s get the sunshine baking—crank your oven to 170°C (340°F) conventional and feel the kitchen hum with promise. Grab three 8-inch baking pans—line the bottoms with parchment (I love that extra slip!). Take a sec to breathe—this is gonna be a zesty wonder, and you’re already on your way.

Step 2: Mix the Dry Goods
In a bowl, sift 340 g all-purpose flour, 2 tbsp cornstarch, ¾ tsp baking powder, ¾ tsp baking soda, and ¾ tsp salt—give it a good whisk (I love that floury puff!). This is the fluffy foundation—set it aside and feel the cake vibes starting.

Step 3: Zest and Cream
In a big mixing bowl, rub 300 g granulated sugar with the zest of one large lemon (or two small) ‘til it’s like wet sand—smell that lemony burst (I grin every time it blooms!). Add 180 g room-temp butter—mix on high with a stand mixer for 3 minutes ‘til light and fluffy (my kitchen’s buzzing with zest!).

Step 4: Add the Wet Mix
Add 4 large room-temp eggs two at a time—mix on low ‘til combined (I love that smooth swirl!). Add half the dry mix—mix ‘til just blended, then add 240 g room-temp sour cream, 60 g vegetable oil, 2 tbsp lemon juice, and 2 tsp vanilla—mix ‘til smooth, then add the rest of the dry mix (I feel pro layering it in!). Fold gently with a spatula ‘til no streaks remain (I’m gentle here—it’s all love!).

Step 5: Bake the Layers
Divide the batter evenly between your three pans—smooth the tops with an offset spatula (I feel artsy leveling it!). Bake for 20-23 minutes—check ‘til a tester’s clean and they stay light (I watch with glee!). Cool in pans 10 minutes—turn onto racks and let cool completely (I’m drooling already!).

Step 6: Whip the Buttercream
In a big bowl, beat 400 g room-temp butter for 4 minutes—add 660 g sifted powdered sugar and 2 tbsp freeze-dried strawberry powder in two parts, with 2-3 tbsp whole milk and 2 tsp vanilla between each (I love that pink swirl!). Scrape and beat 2 more minutes on low—adjust with more milk if needed (I sneak a taste—it’s berry heaven!).

Step 7: Assemble the Cake
Place one cooled layer on a plate—spread two big scoops of buttercream, smooth with an offset spatula, stack the next, repeat, then top with the third (I feel like a stacking pro!). Apply a thin crumb coat—chill 20 minutes to set (I count the minutes with glee!).

Step 8: Frost and Decorate
Frost the whole cake with the remaining buttercream—smooth it out or make waves with the spatula (I swirl it with joy!). Top with fresh strawberries and lemon slices—slice and serve (that first bite’s pure bliss, and you made it happen!). Store in the fridge—bring to room temp for best taste!