Get out and measure all of your ingredients.
Butter or spray a square 8x8 or 9x9 pan and line with parchment paper. This will make for easy removal of the set fudge. Set aside.
In a microwave safe bowl heat chocolate chips and sweetened condensed milk on high for 1 minute and 30 seconds.
Remove from microwave. Let sit for 1 minute and then stir to combine.
If needed put back in the microwave and heat an additional 30 seconds.
Stir until chips are completely melted and chocolate is smooth.
Add vanilla extract and combine.
Add walnuts or pecans, if using.
Pour fudge into prepared pan.
Place pan in fridge for at least an hour to cool and set.
Make sure fudge has cooled completely. Remove from fridge and get ready to cut your fudge into pieces.Next, slice into squares.
Enjoy every bite!