Preheat the oven to 350°F with the rack in the center. Line the bottom of a 9-inch springform pan with a parchment paper circle.

Place the chocolate sandwich cookies (with the cream filling intact) into the bowl of a food processor. Process until finely crushed (scrape down the sides as needed to get them to crush evenly). You can also crush them manually in a large, sealed plastic bag using a rolling pin to smash them up.

Add the melted butter and process again to combine into a chocolatey paste. Transfer the mixture to the prepared springform pan and carefully press it evenly against the bottom (don’t go up the sides). Bake for 10 to 12 minutes. Cool completely before using.

Soften the ice cream at room temperature for about 10 to 15 minutes, but don’t let it melt.

Transfer the softened ice cream to the bowl of an electric mixer fitted with the dough hook. Mix it on low for a couple minutes to soften it a bit more and then add the macadamia nuts and continue to mix until combined.

Transfer the vanilla macadamia nut ice cream to the prepared bowl lined with plastic wrap. Smooth out the top. Carefully place a small cutting board over the cookie crust and then flip it over to invert. Then gently slide it onto the bowl so it fits over the ice cream. It should fit just inside the rim of the bowl. Very gently press it down to make sure it lays flush against the ice cream. Fold the plastic wrap overhang over the cookie crust to seal it in. Freeze at least 8 hours or overnight.

Work quickly so the ice cream stays as cold as possible!

Remove the bowl from the freezer and peel away the plastic wrap covering the cookie base. Gently invert the bowl onto a parchment paper lined board or platter (I use a pizza pan) that can fit inside your freezer. Lift up the bowl and carefully remove all the plastic wrap from the ice cream dome.

Immediately spread 1 cup of room temperature fudge topping over the surface of the ice cream dome. It works best if you dump all the fudge on top and then quickly start spreading rather than doing a little fudge at a time (like frosting a cake). You do not want the fudge to be too warm (it will melt the ice cream and just slide off) or too cold (if it’s solid you won’t be able to spread it. This is the trickiest step. If you find your ice cream is melting and the fudge is sliding off, put the ice cream dome back into the freezer until very very cold and then try again. Freeze until the fudge firms up, about 1 hour or longer.

Remove the assembled Hula Pie from the freezer. Cut into slices with a large sharp knife. Place each slice on a plate and top with hot fudge (gently heated so it’s warm enough to drizzle but not so warm it will melt the ice cream). Sprinkle with chopped macadamia nuts, and finally, garnish with whipped cream piped on the back in vertical lines to resemble a hula skirt.