Step 1

Melt butter in a large saucepot or Dutch oven over medium high heat. Add chopped ham and cook, stirring occasionally, until ham begins to brown, about 4 minutes. Remove ham from pot with a slotted spoon, then return pot to heat and add leek and onion, scraping up browned bits from the bottom of the pot with a wooden spoon. Add carrot, celery, bay leaves, and thyme, and continue to stir until ingredients are well combined. Place ham hocks, pinch of red pepper flakes,and green split peas in the pot and cover with 8 cups of water (or broth, if using). Bring to a simmer, cover, and cook for 1 hour.

Step 2

Remove hocks from the pot and allow to rest until cool enough to handle. Shred meat from bones. Add shredded meat and reserved ham back to the soup and season to taste with salt and pepper. Season with lemon juice to taste. Serve hot with sour cream or yogurt, as desired.