Preheat oven to 400ºF.

Place potato halves on a foil covered baking sheet. Drizzle with 1/2 the oil, cover with foil, and bake for about 30-45 minutes, until fork tender.

While potatoes are baking, in a small skillet, over medium-high heat, sauté onion with remaining oil. Cook for about 5 minutes, until translucent and fragrant.

When potatoes are fork tender, remove from the oven. Spoon beans over each potato. Layer with sautéed onions, feta, and generously garnish with chives. Sprinkle with salt.

Place potatoes back in the oven for about 5-10 minutes, to warm the bean filling and melt the feta cheese. Remove and serve.