- 2 (8 ounce) packages finely chopped walnuts, or more to taste
- 3 (16 ounce) packages semisweet chocolate chips
- 1/2 cup unsalted butter, melted
- 2 tablespoons unsalted butter, melted
- 1 tablespoon maple-flavored extract
- 1/2 (16 ounce) package marshmallows
- 1 teaspoon peppermint extract, or more to taste
- Preheat oven to 350 degrees F (175 degrees C). Spread walnuts on a baking sheet.
- Toast walnuts until fragrant, about 6 minutes. Stir and continue toasting until browned, about 9 minutes more.
- Place chocolate in a microwave-safe bowl. Heat in the microwave in 20-second intervals, stirring after each interval, until mostly melted, about 2 minutes. Stir in 1/2 cup plus 2 tablespoons butter and maple-flavored extract.
- Grease an 8×14-inch baking pan. Pour in half of the chocolate mixture. Add marshmallows and half of the walnuts; press into the chocolate using a spatula.
- Mix peppermint extract into remaining chocolate mixture. Scrape into the baking pan and press in remaining walnuts. Press layers together using a spatula. Cool fudge to room temperature, 1 to 2 hours.