In a medium saucepan, combine maple syrup, coconut oil, peanut butter, brown sugar, vanilla extract, and salt. Heat over medium-low heat until the coconut oil melts and the sugar dissolves, stirring until smooth.
Transfer the mixture to a 9-inch square casserole dish or baking pan lined with parchment paper. Press the mixture firmly and evenly into the pan using a spatula or the back of a glass. Make sure it is tightly packed.