Step 1: Bake the Funfetti Cake

1. Preheat oven to 350°F (175°C). Butter and line a quarter sheet pan with parchment paper.
2. Sift together cake flour, baking powder, and salt in a bowl. In another bowl, whisk buttermilk, oil, and vanilla extract. Set both aside.
3. Cream butter and sugar in a mixer until light and fluffy (~2–3 minutes). Add eggs one at a time, mixing well after each addition.
4. Alternate adding the dry ingredients and buttermilk mixture to the batter in three additions, starting and ending with dry ingredients. Mix until just combined. Gently fold in sprinkles.
5. Spread batter evenly into the prepared pan and sprinkle extra sprinkles on top. Bake for ~25–30 minutes or until the center springs back when touched. Cool completely before cutting.

Step 2: Make the Strawberry Buttermilk Ice Cream

1. Combine strawberries, heavy cream, sugar, buttermilk, lemon juice, vanilla extract, and salt in a food processor. Blend until smooth with no large chunks remaining. Chill the mixture for at least an hour or overnight.
2. Churn the mixture in an ice cream maker according to manufacturer instructions until it reaches soft serve consistency.

Tip: If using store-bought ice cream, let it soften until spreadable.

Step 3: Assemble the Cake

1. Line a 6-inch cake pan with parchment paper on the bottom and an acetate strip around the sides for easy removal.
2. Cut two 6-inch rounds from the cooled funfetti cake using a pastry ring or knife.
3. Place one cake layer at the bottom of the prepared pan. Spread freshly churned (or softened) strawberry ice cream evenly over it.
4. Add the second cake layer on top and press gently to adhere. Cover tightly with plastic wrap and freeze until solid (~4–6 hours or overnight).

Step 4: Decorate and Serve

1. Remove the cake from the pan and peel off acetate or parchment paper.
2. Decorate with whipped topping or frosting, fresh strawberries, and extra sprinkles.
3. Slice using a warm knife (dip in hot water and wipe dry between cuts) for clean edges.