1-Preheat your oven to 350°F (175°C). Grease two 8-inch cake pans thoroughly and dust with flour, lining the bottoms with parchment paper for easy removal.

2-In a large mixing bowl, beat together the granulated sugar, vegetable oil, melted unsalted butter, large eggs, egg yolks, and pure vanilla extract until the mixture is light in color.

3-Add the sour cream (or plain Greek yogurt) to the mixture and beat until combined.

4-In a separate bowl, combine the all-purpose flour, baking powder, baking soda, and salt.

5-Alternately add the dry ingredients and buttermilk (or milk) to the wet mixture, starting and ending with dry ingredients. Mix until just combined, being careful not to overmix.

6-Gently fold in the sprinkles by hand, using jimmies to prevent color bleeding.

7-Divide the batter evenly between the prepared pans. Bake for 25 to 32 minutes or until a toothpick inserted in the center comes out clean.

8-Cool the cakes in the pans for 15 minutes, then transfer to wire racks to cool completely.

1-Allow the ice cream to soften for 15-20 minutes for easier spreading. You want it pliable but not completely melted.

2-Level the cooled cake layers by trimming any domes with a serrated knife. This makes for even stacking.

3-Line an 8-inch springform pan with plastic wrap and place a cake board at the bottom for support.

4-Place one cake layer in the pan and spread the softened ice cream evenly over it, creating a smooth layer.

5-Place the second cake layer inverted on top of the ice cream. This makes the flat bottom of the cake face upward for easier decorating.

6-Wrap the cake tightly with plastic wrap twice to prevent ice crystals from forming.

7-Freeze for 2 to 4 hours until firm. For best results, leave it overnight.

1-Chill a mixing bowl and beaters before starting to help the cream whip properly.

2-Beat the heavy whipping cream until soft peaks form, then gradually add the powdered sugar and sprinkles until stiff peaks form.

3-Transfer the whipped cream to a piping bag fitted with your desired tip.

4-Remove the cake from the pan and pipe whipped cream along the edges and top.

5-Smooth gently with a spatula, and decorate with additional whipped cream and sprinkles as desired.

6-Refreeze the decorated cake for 30 to 60 minutes before serving to make sure the ice cream is firm.