Soak the rolls in plenty of cold water. Clean, wash and finely dice the peppers. Put beans and corn on a sieve, rinse and drain. Mix the vegetables. Peel and finely dice the onions.
Put mince in a bowl. Squeeze the buns. Knead minced meat, onions, eggs and buns. Add the vegetables, except 4 tablespoons, to the minced meat mixture and knead. Season with salt, pepper, paprika and parsley.
Cover an angular springform pan (24 x 24 cm) from the outside with aluminium foil. Put chopping mass into the form and smooth it down. Cook in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 1 hour.
Take out the minced cake and let it cool down a little. Wash the parsley, dab dry and pluck the leaves from the stalks. Garnish minced meat with remaining vegetables, tacos and parsley leaves. Serve with salsa sauce.