Line a 9x13 baking dish with aluminum foil, leaving enough extra to hang over the edges.
Melt the butter and chocolate in a microwave safe bowl and melt in 30 second intervals, stirring between each blast. When melted and smooth, set aside.
Pulse the cookies and sugar in a food processor until finely ground crumbs.
Through the feed tube, with the processor still running, drizzle the melted chocolate it.
Using your fingers, or the bottom of a glass, press the crumb mix into the bottom of the pan. Place in fridge.
For the filling:
In a small saucepan, warm the lime juice over low heat.
Add the gelatin and sugar and whisk until completely dissolved, remove from heat and cool slightly.
In the bowl of your stand mixer, beat the cream cheese on high speed until smooth, about 4 minutes.
Add the sweetened condensed milk and beat until smooth again.
Mix in the gelatin and vanilla. Mix 30 seconds longer.
Scrape down the edges and give it one more mix.
Pour the filling over the prepared crust, smoothing out the top.