Lightly coat a 6-quart slow cooker with cooking spray.
Add egg whites to slow cooker and whisk the egg whites until foamy. Add the sugar, butter, and spices and stir until a thick syrup forms.
Add nuts and stir to coat the nuts in the syrup. Cover the top of the slow cooker with a clean dishcloth or two layers of paper towels. Place lid on top, then cook on low for 3 to 3 1/2 hours or on high for 1 1/2 to 2 hours, stirring every 20 minutes and every few minutes at the end, until nuts are fragrant, lightly browned, and the coating appears dull and not shiny.
Remove nuts from slow cooker (there will be excess sugar coating left behind.) Spread nuts into an even layer onto 2 parchment-lined baking sheets, spreading them out and separating as much as possible. Cool completely, stirring once or twice so the nuts won’t stick.
Once cool, break apart any nuts that have stubbornly stuck together and transfer to a serving dish, jar for gifting, or airtight container for storage. Store in an airtight container at room temperature for several weeks. If nuts soften with storage, crisp them by placing in a 400 degree F. oven for 10 to 15 minutes, stirring often.
Keywords: Appetizer, Candy, kitchn, Midwest Living, nuts, Slow Cooker