Preheat oven to 350 F
For the crust, mix all ingredients together in a bowl. Flatten into an 8 x 8 baking dish lined with parchment paper.
Bake the crust for 12-15 minutes, until it starts to brown around the edges. Remove from oven and let cool for 5 minutes before topping with the caramel.
For the caramel layer, whisk together the nut butters, maple syrup, coconut oil and vanilla until smooth in the same bowl you used for your crust.
Gently pour over the crust. I use a wet spatula to spread it around so that it doesn't break into the crust.
Freeze the bars for 1-2 hours, until firm enough to cut.
Once they're frozen, melt the chocolate chips with the coconut oil and coat over the caramel layer. Return to freezer for 5 minutes to harden.
Once the chocolate hardens, slice the bars using a large knife. I first cut it in half vertically, then horizontally, then make two cuts horizontally on top and on the bottom to make 16 bars.
Top with sea salt. Keep stored in freezer for up to 3 months for a more firm texture, or refrigerate for 2 weeks for more of a caramel texture.