Both waste-not books compared in Green Plate Special this week offer recipes for one of my favorite ways to repurpose mashed potatoes. In “Waste Not, Want Not,” Helen McCully makes potato cakes as I would – with sautéed onion, an egg and breadcrumbs, which makes a perfect side dish. But this recipe, adapted from Bryant Terry’s in the James Beard Foundation’s “Waste Not” cookbook, includes enough protein to turn them into a main dish. Terry, a vegan chef, uses ground flax seeds as a binder. In line with the not wasting theme, and not running out to the store needlessly, I used the egg I had in the refrigerator instead.

Makes 4 to 6 cakes

¼ cup vegetable oil

¾ cup finely chopped yellow onion

2 garlic cloves, minced

1 teaspoon harissa

1 egg

3/4 cup cooked red lentils

1 1/2 cups cooked quinoa

¾ cup mashed potatoes

1 teaspoon salt

1 1/2 cups fresh bread crumbs

Tossed salad for serving

Heat 2 tablespoons of oil in a sauté pan over medium heat. Add onions and cook until softened, 4-5 minutes. Add garlic and harissa, stir to combine and cook for 1 minute more. Transfer onion mixture to bowl and cool slightly. Add egg and combine very well. Add lentils, quinoa, potatoes and salt. Stir to combine. Form into 4 or 6 patties. Spread breadcrumbs on a plate. Coat each potato cake on both sides with breadcrumbs, pressing them gently into the cake.

Heat remaining 2 tablespoons oil in sauté pan over medium high heat. Place cakes in hot pan and cook until crumbs are golden brown on one side, 4-5 minutes. Flip and cook until the crumbs on both sides are golden brown, another 4-5 minutes.

Serve hot with tossed salad.