Prepare the Walnuts: Begin by preheating your oven to 350°F (175°C). Spread the walnuts evenly on a baking sheet to ensure they toast uniformly. Place the baking sheet in the oven and roast the walnuts for about 10 minutes. To prevent uneven browning or burning, gently toss or stir the walnuts every few minutes. You’ll know they’re ready when they take on a light golden-brown color and release a nutty aroma. Once toasted, remove the walnuts from the oven and allow them to cool slightly before roughly chopping them into bite-sized pieces. Setting them aside for later use in the ice cream is essential for adding delightful texture and flavor.
Whisk the Egg Yolks: In a large mixing bowl, carefully separate 5 egg yolks from the whites, reserving only the yolks for this recipe. Using a whisk, beat the yolks vigorously until they become lighter in color and slightly thickened. This step helps incorporate air, making your custard base smooth and rich. Set the bowl aside for now, as you will slowly incorporate the heated dairy mixture next.
Reduce the Maple Syrup: Pour 1 cup of high-quality maple syrup into a medium saucepan and place it over medium heat. Bring the syrup to a gentle boil, then reduce the heat to low and let it simmer. Allow the syrup to reduce until it reaches about ¾ cup in volume—this concentration step intensifies the maple flavor for a richer taste. You can reduce it further to around ½ cup if you prefer a more robust sweetness. Stir occasionally to prevent burning and keep the syrup smooth.
Heat the Dairy Mixture: Once the maple syrup has reduced, add 1 cup of heavy cream, 1 cup of whole milk, and a pinch of salt to the saucepan. Increase the heat to medium and whisk gently but continuously until the mixture is hot—just below boiling point. This warming process blends the flavors and prepares the dairy for the custard base.
Temper the Egg Yolks: Slowly and carefully, begin adding the hot maple cream mixture to the whisked egg yolks in a thin, steady stream. This gradual addition—known as tempering—prevents the eggs from scrambling by gently raising their temperature. Whisk continuously and patiently until the mixture is fully combined and smooth. For an ultra-silky texture, strain the mixture through a fine mesh sieve to remove any lumps or bits of cooked egg.
Reheat the Custard Base: Return the strained custard mixture to the saucepan over medium-low heat. In a separate bowl, combine the remaining 1 cup of heavy cream with 1 tablespoon of cornstarch until smooth. Slowly pour this cornstarch-cream mixture into the saucepan, whisking continuously. Gently reheat the custard while stirring occasionally, taking care not to let it boil, as boiling can curdle the mixture. When the custard thickens slightly and coats the back of a spoon, remove it from heat and allow it to cool to room temperature. Stir occasionally during cooling to prevent a skin from forming.
Chill Overnight: Once cooled, cover the custard base tightly with plastic wrap or transfer it to an airtight container. Refrigerate overnight or for at least 8 hours. This resting period helps deepen the flavors and allows the mixture to thicken, ensuring a creamy texture when churned.
Churn the Ice Cream: Prepare your ice cream maker according to the manufacturer’s instructions. Pour the chilled custard mixture into the machine’s bowl. Start churning, allowing the machine to aerate and freeze the mixture until it reaches a soft-serve consistency, usually about 20-30 minutes depending on your machine. In the final 5 minutes of churning, slowly add the toasted, chopped walnuts to evenly distribute them without losing their crunch.
Freeze for Firmness: Transfer the churned ice cream into a freezer-safe container. For extra indulgence, drizzle additional maple syrup over the top and sprinkle with more chopped walnuts if desired. Seal the container and place it in the freezer for at least 2-4 hours to firm up the ice cream to a scoopable consistency.
Serve and Enjoy: Before serving, remove the ice cream from the freezer and let it sit at room temperature for about 10 minutes. This softening period makes scooping easier and enhances the creamy texture. Scoop into bowls or cones and savor the rich maple flavor paired with crunchy walnut bites—a perfect homemade dessert experience.
