Ingredients

• 6 tablespoons unsalted butter
• 1/3 cup blanched hazelnuts
• 4 thyme sprigs
• 1 pound russet potatoes, peeled, cut into 1-inch pieces
• Kosher salt
• 2 pounds kohlrabies, peeled, cut into 1/2-inch pieces
• 1/3 cup heavy cream

Instructions

1. Heat butter in a small saucepan over medium. Cook hazelnuts until butter foams, then browns, about 5 minutes. Add thyme sprigs and cook until crisp, about 30 seconds. Immediately transfer to a bowl; spoon out nuts and coarsely chop.
2. Meanwhile, place potatoes in a large pot and pour in cold water to cover by 1". Season with salt; bring to a boil. Reduce heat and simmer until very tender, 10–12 minutes. Transfer to a large bowl. Return water to a simmer; cook kohlrabies until tender, 12–14 minutes. Drain and add to bowl with potatoes.
3. Heat cream in a small saucepan over medium until warm.
4. Pass potatoes and kohlrabies through potato ricer or food mill into a large bowl (alternatively, you can also use a masher). Stir in brown butter and warm cream; season with salt. Top mash with hazelnuts and crumble fried thyme over.