This custard-style ice cream is for devoted black walnut lovers, and wannabe lovers. It gives a double dose of the nut’s unique flavor: First, toasted nuts are ground into a flour and steeped in the cream and milk to impart their flavor, sight unseen; second, at the end of churning, finely chopped toasted black walnuts are mixed in for crunch and another layer of flavor. A few extra steps are involved in making this ice cream—like tempering the egg yolks and reducing the maple syrup—but the results are worth it. Ever since researching the inimitable black walnut for my blog posting “Black Walnuts—A Story of Love Lost and Regained,” I’ve wanted to take the time to perfect a maple black walnut ice cream recipe. Now I’ve done it, just in time for the last dog days of summer.

 

Maple Black Walnut Ice Cream

Makes 1½ quarts

 

4 ounces (1 scant cup) black walnut meats (see Sources, below)

2¾ cups whole milk

1¼ cups heavy cream

¼ teaspoon coarse sea salt

¾ cup plus 2 tablespoons pure dark maple syrup (see Sources, below)

6 large egg yolks

 

1. Preheat the oven to 325°F. Toast the nuts in the oven until lightly browned and fragrant, 6 to 8 minutes. Allow the nuts to cool, then grind one-third of them into a flour. (Note: Because of their high fat content, black walnuts go from flour to nut butter very quickly, so have a light finger on the pulse button.) Reserve the remaining toasted nuts in an airtight container.
2. Put the nut flour in a heavy bottomed saucepan along with the milk, cream, and salt. Bring just to a simmer over medium heat. Remove from the heat and let steep for 30 minutes.
3. Meanwhile, reduce the maple syrup: Put the maple syrup in a 3- to 4-quart heavy bottom saucepan. Bring to a simmer over medium heat, then continue to simmer until reduced to ⅔ scant cup, 8 to 12 minutes. (The exact time depends on the diameter of your pan, and how rapidly you simmer the syrup.) Watch carefully as syrup as can easily boil over (stir the syrup with a heatproof spatula or slide the pan off the heat if needed to keep the syrup from bubbling up and over the pan).
4. Strain the milk-cream mixture through a fine-mesh sieve into in the 3- to 4-quart saucepan with the reduced maple syrup, pressing against the nut flour pulp to extract the liquid; discard the pulp. Gently heat the syrup mixture until steam is rolling off the surface, stirring to release any caramelized bits of sugar from the bottom and sides of the of the pan and dissolve them into the milk and cream.
5. In a heatproof mixing bowl, whisk the egg yolks vigorously for a minute, until frothy.
6. Whisking constantly, gradually ladle half of the hot milk-cream mixture into the yolks to temper the eggs.
7. Add the tempered yolk mixture to the saucepan with the remaining milk and cream mixture and whisk to blend.
8. Return the pan to the heat and cook over medium to medium-low heat, stirring constantly with a wooden (or heatproof silicone) spatula in a figure eight motion, until it reaches 165°F to 175°F. At this point the cream will coat the back of the spoon and be noticeably thickened. (To sterilize the egg yolk, keep it at 170°F for 1 minute.) When stirring the pan, be sure to get the spoon into the bottom corners of the pan as that is where the egg will coagulate first. Do not let it come to a boil; if the mixture is heated to 180°F it will curdle.
9. Strain the custard through a fine-mesh strainer and set in a bowl over ice water. Stir until cooled, then refrigerate for several hours to chill thoroughly.
10. When you’re ready to churn the custard, finely chop the remaining toasted black walnuts. Process the custard in an ice cream maker, following the manufacturer’s instructions. Add the finely chopped nuts to the ice cream during the last 1 to 2 minutes of churning time. Once churned, transfer to a container and place in the freezer to set up for 4 hours before serving. For best flavor and texture, allow to soften for 5 or 10 minutes before serving.

 

SOURCES

For black walnuts:

My year-round source for black walnuts is Hammons Nuts. I like to buy them directly from Hammons because they keep them in cold storage until they’re shipped out. Another good option is to look for black walnuts on the shelf at your local supermarket in the late fall, after the new fall crop has been harvested, processed, bagged, and shipped out to stores.

 

For maple syrup:

I like to buy food directly from farmers when possible, partially because it’s the right thing to do (they benefit economically from direct sales), and partially because I enjoy having a relationship with the people who make the food I eat. I was lucky to live in the land of maple syrup for several years, and used to buy directly from these two sugar makers:

 

Silloway Maple

Krueger-Norton Sugarhouse

 

But you don’t have to live in Vermont to enjoy their syrup and other maple products. Both Silloway Maple and Krueger-Norton Sugarhouse do mail order sales. To find other sugar makers in Vermont that do mail orders, visit the site of the Vermont Maple Sugar Association.