1/4 cup walnuts
1/2 cup Deglet Noor or Medjool dates, pitted
Pinch of ground cinnamon
Pinch of kosher salt
1 cup vanilla ice cream
Preheat oven to 350°. Toast walnuts on a rimmed baking sheet, tossing once, until slightly darkened in color and fragrant, 8–10 minutes. Let cool.
Meanwhile, place dates in a small bowl and add ½ cup hot water to cover; soak 10 minutes to soften.
Blend walnuts, dates with their soaking liquid, cinnamon, and salt in a blender until a coarse paste forms. Add ice cream and ¾ cup cracked ice and blend until smooth. Divide shake between 2 glasses.