Line the pan with parchment paper and coat with cooking spray.
In a small bowl, mix the tahini and maple syrup together.
Combine the chocolate chips and sweetened condensed milk in a double boiler over medium heat. Heat until melted, about 5-7 minutes. Add salt and stir until smooth.
Remove from heat (you need to get it into the pan as quickly as possible) and pour the chocolate mixture into the prepared pan. Smooth the top with a rubber spatula.
Spoon dollops of the sweet tahini over the surface of the pan and use a knife or a skewer to swirl it into the brownies.
Refrigerate until set, minimum of 2 hours (ideally overnight).
Holding the parchment paper, lift the fudge from the pan, and cut it into small squares.
The best way to keep fudge fresh is by transferring it to an airtight container and storing it at room temperature. Layer the fudge with waxed paper and store it in an airtight container. It’s best to keep the fudge somewhere cool and dry to avoid it from melting. Refrigerating fudge can extend its shelf life to two to three weeks. Freezing fudge will extend its shelf life to around three months if tightly sealed.