Arrange 30 crackers in a single layer on the bottom of a 9x13-inch pan.
Add butter, brown sugar, and white sugar to a saucepan over medium heat and bring to a simmer, stirring often.
Add milk, salt, and vanilla and stir until well combined.
Cook for 2 minutes and remove from heat.
Pour half of sugar mixture over crackers and top with 30 more crackers.
Pour remaining sugar mixture over and top with remaining crackers.
Place chocolate chips and coconut oil in a microwave safe bowl.
Microwave on High in 20- to 30-second intervals, stirring in between, until just melted.
Pour melted chocolate over the top layer of crackers and spread evenly all the way to the edges.
Refrigerate until set, at least 30 minutes.
Cut into 30 bars.
