Add the Oreos to a food processor and pulse until you have fine crumbs. Transfer to a bowl, stir in the melted butter, and mix until evenly moistened.

Press the mixture firmly into the bottom of a 9-inch springform pan lined with parchment paper. Chill in the fridge while you make the filling.

Make the cheesecake filling: 
In a large bowl, beat the softened cream cheese and sugar until smooth and creamy. Scrape down the sides of the bowl as needed to make sure there are no lumps. Mix in the vanilla extract and lemon juice.

Gradually pour in the heavy cream in 3–4 additions, whipping after each one. Keep beating until the mixture turns light, fluffy, and holds soft peaks.

Pour the cheesecake filling over the chilled crust and smooth out the top with a spatula. Cover the pan with plastic wrap and refrigerate for 8–12 hours, or overnight, until fully set. Add sprinkles.

In a heatproof bowl (or the bowl of a stand mixer), combine the egg whites, sugar, and salt. Set the bowl over a pot of simmering water, making sure the bottom doesn’t touch the water. Gently whisk for about 4 minutes, or until the sugar is dissolved and the mixture is warm to the touch. Rub a bit between your fingers—it should feel completely smooth.

Transfer the bowl to your stand mixer and beat on medium-low until foamy. Increase the speed and continue whipping until stiff, glossy peaks form and the bowl feels cool to the touch, about 4–5 minutes. Add the vanilla and mix just to combine.

Pipe the meringue around the edges of the cheesecake and torch it until golden brown. It gives the cake that toasted marshmallow vibe and helps hold the shape.