Put large pot (Dutch oven) on burner set on high and let heat a few minutes. Put pork in pot, let brown about 5 minutes. Place cubed potatoes in pot, stir and cook 10 15 minutes. Add spices and beans, cook 5 minutes. Place stock in pot and cover; turn heat to medium and cook 10 minutes. Check temperature of pork. At 160F, mix in lemon juice. When serving, garnish with feta cheese.