Line an 8x8" square pan with parchment paper, leaving some overhang on the sides. Lay down about 6 graham cracker sheets to cover the bottom—trim a couple if needed to make them fit snugly.

In a mixing bowl, whisk together the pudding mix, cold milk, and Greek yogurt (or coconut cream) for about 2 minutes until thickened. Spread this evenly over the graham cracker base. Freeze for 15–20 minutes to set slightly.

In a chilled bowl, whip the heavy cream (or cold coconut cream) until soft peaks form. Gently fold in the marshmallow fluff and vanilla extract until smooth, fluffy, and spreadable.

Spread the marshmallow mixture over the chilled chocolate layer. Make sure it’s even and reaches the corners of the pan.

Place the remaining graham cracker sheets on top, lining them up to match the base layer. Press down gently so they stick to the marshmallow.

Cover tightly and freeze for at least 6 hours, preferably overnight, until fully set.

Let the bars sit at room temp for 5–10 minutes before slicing. Use a sharp knife and cut along the graham cracker lines. Wipe the knife between slices for cleaner edges.