Try this Oreo Poke Cake recipe
Package directions omit the structural physics governing liquid-soaked desserts. Standard cake crumb acts as a sponge. Pouring liquid pudding into pierced channels relies on capillary action to saturate the interior uniformly. Cold milk activates the instant pudding thickener rapidly. Whisking must occur immediately before pouring to prevent premature setting in the bowl. Coarseness of the cookie crumble directly influences moisture retention. Large pieces maintain structural integrity longer against damp crumbs, whereas fine dust dissolves into sludge. Greasing the 9x13 dish thoroughly with shortening prevents the bottom crust from bonding to the metal pan during the 350 degree bake. Freezing this dessert is not recommended. Dairy-heavy pudding structures and whipped toppings separate upon thawing, yielding a watery separation that ruins the crumb. Refrigeration must happen promptly after assembly. Chill the pan for at least one hour to allow the starch networks to firm up fully. Consume the chilled cake within 48 hours for optimal texture. Extended refrigeration past three days compromises the crisp exterior of the topping cookies, turning them soggy as moisture migrates from the pudding layer.