"I love to buy beets at the farmers market, because we can eat the roots and the greens. This is a recipe I made to introduce my kids to eating the greens, and they loved it! This soup is wonderful topped with sour cream or plain yogurt, and served with warm bread."
Place potato in a microwave-safe bowl. Cover with salted water. Cook in the microwave until tender, about 5 minutes.
Place beet tops and stems on a flat work surface. Cut greens into thin strips and dice stems. Stack greens and stems in separate piles.
Heat bacon grease in a large skillet over medium-high heat. Add beet stems, onion, and carrots. Cook and stir until tender, about 5 minutes. Season with salt. Add beet greens; saute until wilted, about 5 minutes.
Reserve 1/2 cup of the greens mixture in the skillet. Transfer the rest of the mixture into a blender; add boiled potato and 2 cups stock. Blend until smooth, adding salty potato water to thin mixture as needed.
Pour the blended mixture into a large pot. Stir in the reserved greens mixture, the remaining 2 cups stock, shredded pork, and peas. Cook until soup is heated through, about 8 minutes. Season with salt and pepper.