Line an 8x8-inch baking dish with aluminum foil, being sure to allow a little extra to hang over the sides.

In a medium saucepan, over low heat, melt the white chocolate chips, sweetened condensed milk, and butter. Be sure to stir constantly to avoid burning the white chocolate chips. This should take about 5-6 minutes.

Once the mixture is smooth and fully melted, remove it from the heat and stir in the maple extract and 1 cup of the chopped walnuts.

Working quickly, spread the fudge mixture into an even layer in the prepared pan. Top the fudge with the remaining 1/2 cup of chopped walnuts. Gently press the chopped walnuts into the fudge using your fingers tips. This helps them to stick to the fudge when slicing.

Allow the fudge to cool on the counter before placing it in the refrigerator to fully set up and chill. Once ready, gently lift the fudge from the pan (using the overhanging aluminum foil as a handle) and slice it into 1-inch pieces. (To cut your fudge, it’s best to use a large chef knife. You can warm the knife by running it under warm water, then dry it off with a towel before slicing.)

Store the fudge in the refrigerator in an airtight container for up to two weeks. Allow your fudge to come to room temperature before serving for a softer texture.

To Freeze: This fudge can be frozen for up to 2 months. Wrap it in parchment paper, then tightly wrapping it in aluminum foil for best storage results when freezing.