Clean, wash and chop the peppers. Cut the corncobs into slices. Peel onions and cut into slices. Pour beans into a sieve, rinse with cold water and drain.
Peel, wash and slice the potatoes. Clean, wash and cut the chillies into fine rings. Wash the meat and dab dry. Heat oil in portions in a large pan, fry meat in it in 2 portions on both sides, season with salt and pepper, remove.
Add potatoes and onions to the frying fat, fry while turning, add chilli rings and oregano, season with salt and pepper, remove. Add the bell peppers and corn to the pan and fry. Deglaze with broth and bring to the boil.
Mix in the beans. Put meat, potatoes and vegetables with broth in a roasting pan. Cover and bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 1 3/4 hours.
Remove the lid 15 minutes before the end of the cooking time. Garnish with marjoram.