One easy marshmallow fudge recipe requires you to combine sweetened condensed milk and semi-sweet chocolate chips in a saucepan, and heat until the chocolate is melted. Add in vanilla extract and miniature marshmallows, then pour into a prepared pan. Refrigerate until set, then cut the fudge into squares to serve.
To make the fudge batter, add 1 14-ounce can of sweetened condensed milk and 1 12-ounce bag of semi-sweet chocolate chips to a saucepan. Place over low heat, and stir until the chocolate is completely melted and combined with the milk. When the mixture is smooth, remove from the heat. Stir in 1 teaspoon vanilla, then fold in 1 cup of mini marshmallows. Stir just until the marshmallows are mixed into the fudge. Avoid overmixing, or the marshmallows will start to melt.
Grease the bottom and sides of an 8-by-8-by-2 inch pan with butter, then pour the fudge mixture into it. Smooth the top slightly, then place in the refrigerator for at least 1 1/2 hours to set. Cut the fudge into 1-inch cubes before serving. You can prepare marshmallow fudge with other types of chocolate, such as milk or dark chocolate. You can also add in chopped nuts like peanuts, pecans or walnuts.