Grilled Sirloin with Green Tomato and Melon Salad

Ingredients

• 150 gm lightly salted butter, at room temperature
• 2 tbsp harissa paste
• 2 tbsp finely chopped preserved lemon
• 2 sirloin steaks (250gm each), at room temperature
• Green tomato and melon salad
• 2½ tbsp sherry vinegar
• 60 ml (¼ cup) extra-virgin olive oil, plus extra for drizzling
• 1 small red shallot, finely chopped
• 3 small green tomatoes, thinly sliced
• 350 gm honeydew melon, peeled and thinly sliced (approx ¼ melon)
• 1 Lebanese cucumber, thinly sliced
• 20 gm pickled watercress
• Baby parsley leaves, to serve