Place the pork steaks between 2 sheets of plastic wrap. Use a meat mallet or rolling pin to pound until 1cm thick.
Reserve ½ cup of the parsley leaves. Finely chop remaining ¼ cup of parsley. Combine chopped parsley, breadcrumbs and fennel seeds in a medium bowl. Place the flour and egg in separate bowls. Dip a pork steak in the flour to lightly coat. Dip in egg, then in the breadcrumb mixture, pressing to coat. Repeat with remaining pork steaks.
Add enough oil to a large deep frying pan to come 1cm up the side of the pan. Heat over medium heat. Cook the pork, in batches, for 2 mins each side or until golden brown and cooked through. Transfer to a plate lined with paper towel.
Meanwhile, cook the potato in a large saucepan of boiling water for 15 mins or until tender. Drain. Set aside to cool slightly.
Combine mayonnaise, peppercorns and 1½ tbs warm water in a small bowl. Season. Combine potato, fennel, onion, rocket and reserved fennel fronds and parsley leaves in a large bowl. Drizzle with dressing. Toss to combine. Divide among serving plates. Serve with schnitzel and lemon wedges.