Line an 8-inch square baking pan with lightly greased parchment paper or non-stick foil and set aside. 

In a microwave-safe bowl, place the chocolate chips. Microwave at 70 percent power for 90 seconds. Stir, using the residual heat to fully melt the chocolate until smooth. If needed, microwave at 30 second, then 15 second intervals additionally. 

Stir the sweetened condensed milk into the chocolate until the mixture is very smooth.

Pour the mixture into the prepared baking pan. Top with pretzels. You should fit 4 to 5 pretzels across and 5 pretzels down for an 8-inch pan. 

Sprinkle the fudge with 2 to 3 pinches of coarse sea salt.

Chill the fudge in the refrigerator until well set, about 2 hours.

Cut into squares so one whole pretzel is on each square of fudge.