Line an 8-inch square pan with parchment paper, extending paper over edges of pan.
Scrape seeds out of vanilla beans and sit aside.
Melt white chocolate squares with sweetened condensed milk in heavy saucepan over low heat. Remove from heat; stir in vanilla seeds and vanilla extract
Spread a about 1/3 of fudge evenly in prepared pan.
Spread caramel sauce over fudge in pan.
Sprinkle half of salt over caramel sauce.
Spread remaining fudge over caramel sauce.
Sprinkle remaining salt over the top of fudge.
Chill for 2 hours or until firm. Remove from pan by lifting edges of wax paper. Cut into squares. It will be messy!