Let’s assemble this impressive Peaches and Cream Ice Cream Cake:

1. Prepare Your Pan and Crust:

• Lightly butter a 9-inch springform pan. Line the bottom of the pan with a circle of parchment paper cut to fit.
• Arrange the 8 to 10 oatmeal raisin cookies in a single, even layer to cover the bottom of the pan. Break cookies as needed to fill in any gaps.
• Sprinkle ½ cup of the granola evenly on top of the cookie layer.

2. Layer the Ice Cream:

• Remove the peach and vanilla ice cream from the freezer and let them soften at room temperature for about 10-15 minutes, until they are soft enough to scoop and spread easily, but not melted.
• Using a large ice cream scoop, alternate scoops of the softened peach ice cream and vanilla ice cream over the cookie and granola crust. This will create a lovely marbled or checkerboard effect.
• Pack the scoops in tightly together. Use an offset spatula or the back of a spoon to gently spread and smooth the top into an even layer.

3. Initial Freeze:

• Cover the springform pan tightly with plastic wrap.
• Place the pan in the freezer on a level surface. Freeze until the ice cream is firm, about 2 to 2 ½ hours.

4. Unmold the Cake:

• Once the ice cream cake is firm, remove it from the freezer.
• Run a thin knife around the edge of the cake to loosen it from the sides of the springform pan.
• Carefully unhinge and remove the springform ring.
• Invert the cake (which is still on its metal base) onto a large sheet of plastic wrap. Carefully remove the bottom of the pan and peel off the parchment paper circle.
• Place your final serving plate or cake stand upside down on the (now top) cookie crust. Holding the cake and the plate firmly together, invert them once more so the cake is right-side up on its serving plate. You can return it to the freezer briefly while you make the frosting.

5. Make the Vanilla Whipped Cream Frosting:

• In a large, chilled bowl, add the 2 cups of cold heavy cream, 2 tablespoons of confectioners’ sugar, and ½ teaspoon of pure vanilla extract.
• Using an electric mixer (with whisk attachments), whip on medium-high speed until soft peaks form. Soft peaks are when the cream holds its shape but the tip gently curls over when the beaters are lifted.

6. Frost and Garnish the Cake:

• Working quickly, frost the top and sides of the frozen ice cream cake with the freshly made vanilla whipped cream frosting.
• Sprinkle the remaining ¼ cup of granola over the top and/or around the base for decoration.
• If the cake or frosting begins to get too soft at any point during this process, return it to the freezer for a few minutes to firm up.

7. Final Freeze:

• Place the fully frosted cake back into the freezer for another 1 ½ to 2 hours, or overnight, to allow the whipped cream frosting to freeze and become firm.

8. Serve:

• Before serving, let the fully frozen cake sit at room temperature for about 20 minutes. This is a crucial step to soften it slightly, making it much easier to slice.
• Slice into wedges with a large, sharp knife (dipped in hot water for clean cuts) and serve immediately.

Patience with the multiple freezing steps is the key to a beautiful, sliceable cake!