Line a 9" x 9" pan with parchment paper.
In a microwave-safe bowl, combine sweetened condensed milk, chocolate chips, and extract.
Add other options now, nuts, spicy ingredients, or candy pieces like chopped peppermint.
Microwave in 30-second increments until melted, stirring in between.
Pour into the prepared pan and spread out with a rubber spatula.
Refrigerate until set, about 2 hours.
Remove from pan and cut into small pieces for serving.
Store in the fridge.
For Nutty Fudges:
Stir in 1/2 cup roughly chopped nuts (pecan, walnut, or almond).
Consider replacing all or part of the vanilla extract with the corresponding nut extract.
For white chocolate fudge, replace semi-sweet chocolate chips with white chocolate chips.
For marbled fudge, make half of the recipe with white chocolate chips and the other half with semi-sweet.
Spoon each into a prepared pan to dot the bottom then use a butter knife or toothpick to swirl together.
For mint chocolate fudge, replace vanilla extract with 1 teaspoon mint extract.
Making this "homemade gift" is a great economical way to share your love. Enjoy!