Before you start, preheat oven to 220°C (or 200°C fan bake).
Prep potatoes and asparagus. Toss potatoes on a lined oven tray with spiced and oil. Season with salt and pepper and roast for 25 minutes. After 25 minutes, remove tray from oven, add asparagus and walnuts to tray with another drizzle of oil and toss together. Return to oven to cook for a further 5-8 minutes, until asparagus is tender and walnuts are toasted.
Meanwhile, prep onion and chickpeas. Heat oil in a large, non-stick fry-pan on high heat. Cook onion and corn for 3-4 minutes, tossing occasionally, until tender and starting to colour. Transfer corn and onion to a large bowl. Wipe pan clean and reserve pan.Add chickpeas to bowl with corn and lightly smash with a masher to crush chickpeas. Add chickpea flour, baking powder, spices, milk and salt and mix well, until combined and no dry spots of flour remain.
Heat oil in reserved fry-pan on medium heat. Using a ¼ cup measure, cook fritters, in batches, for 2-3 minutes each side until golden and cooked through. Add more oil to pan between batches when needed.
To finish, prep lettuce, avocado and basil.
Serve potato salad, lettuce, fritters, mayo and avocado topped with basil.