Pre-chill the Nutella. Scoop Nutella into 12 small teaspoons on a parchment-lined plate. Freeze for 20–30 minutes until firm but not rock hard.
This helps the center stay molten while baking.
Prep your pan. Heat the oven to 350°F (175°C). Lightly grease a mini muffin tin or line with mini paper liners.
Make Oreo crumbs. Add Oreos (cream and all) to a food processor and pulse to a fine crumb. No processor?
Seal in a bag and crush with a rolling pin until sandy.
Mix the dough. In a bowl, combine Oreo crumbs with softened cream cheese. Add melted butter, powdered sugar, vanilla, and a pinch of salt if using. Stir until you have a soft, slightly tacky dough that holds together when pressed.
Portion the base. Scoop about 1 tablespoon of dough per bite.
Press into each well of the mini muffin tin, pushing up the sides to form a small cup.
Add the lava center. Place a frozen Nutella mound into each cup. Gently cover with a thin layer of dough, sealing the edges so the Nutella is enclosed.
Bake briefly. Bake for 8–10 minutes. You’re looking for a set surface with faint gloss and slightly firm edges.
Don’t overbake—soft is good.
Cool just a little. Let the bites rest in the pan for 5 minutes. Transfer to a cooling rack. They should still be warm and gooey inside.
Finish and serve. Dust with powdered sugar or a pinch of flaky salt.
Serve warm for maximum lava effect.