Mix graham cracker crumbs with melted butter.
Add sugar and mix everything well.
Press mixture into tart pan firmly.
Refrigerate for 30 minutes until set.
Heat heavy cream in a saucepan.
Don't let it boil completely.
Remove from heat when it's hot.
Add chocolate chips and let sit 2 minutes.
Stir until chocolate melts completely smooth.
Mix in butter until fully combined.
Add corn syrup and vanilla extract.
Stir everything together until glossy and smooth.
Pour chocolate filling over prepared crust.
Spread evenly with a spatula.
Tap pan gently to remove air bubbles.
Refrigerate for at least 4 hours.