Drain pumpkin and capers separately. Wash the dill and chop finely, except for something to garnish. Wash apple, dab dry, quarter and cut out the core. Cut apple, pumpkin and matie into fine cubes and place in a bowl. Sprinkle with lemon juice
Mix matie, pumpkin, capers, apple and dill. Season to taste with pepper and possibly a little salt. Cover and let it steep for a while
Heat the oil in a large frying pan. Fry the frozen Rösti corners in it for about 4 minutes on each side until golden brown
Arrange 2 Rösti corners on 4 plates. Spread matie tartare on them. Garnish with dill flags and apple slices
Drink: mineral water or cold beer