To make the batter, sift the flour and salt into a mixing bowl, make a well in the centre, add the egg and whisk , gradually adding the milk, until you have a smooth creamy batter. Whisk in the basil and melted butter. Cover and leave to stand for 30 minutes. Meanwhile, preheat the oven to 400°F/200°C/Gas Mark 6. Toss together the onions, peppers, courgettes, , olive oil, garlic and seasoning. Spread into a roasting tin and cook for 30 minutes. Toss well and add the cherry tomatoes. Return to the oven for 5 minutes.
To cook the crêpes, whisk the batter again and using a ladle, swirl a layer of the batter over the pan – slightly thicker than you would normally. Cook for 2 to 3 minutes then flip over with a palette knife and cook the other side for a further 2 minutes. Stack onto a warmed serving dish and keep warm whilst you cook up the remaining batter to make a total of 6 pancakes.
To assemble, place one crêpe onto a baking tray, spread with a little ricotta and top with another crêpe, then top this with some of the roasted veg mixture . Repeat the layers, finishing with a crêpe. Thinly slice the tomato and arrange on top of the crêpe, sprinkle with Parmesan and bake in the oven for 15 minutes.
Serve hot, cut into thick wedges. Garnish with fresh basil leaves.