Mix the mayonnaise with basil pesto and a squeeze of lemon.
Roll the halloumi in the flour so that it’s evenly coated. Heat the oil in a shallow, heavy-bottomed pan or casserole dish until 180C on a cooking thermometer, or a piece of bread browns in 20 secs. Working in batches, carefully lower the halloumi into the oil and cook for 2 mins until crisp and golden, then drain on kitchen paper.
Sprinkle over the mint and parsley and serve with the lemon wedges and the basil pesto mayo for dipping.