Place milk and eggs in a large bowl. Whisk until well
combined. Stand for 15 minutes.
Meanwhile, place oil in a 5cm-deep, 16x22cm metal roasting
pan. Place in oven for 5 minutes or until oil is sizzling.
(The oil needs to be sizzling hot before you add the batter.
This will ensure your pudding is golden and well puffed.)
Add flour to egg mixture. Whisk until well combined.
Carefully pour batter into sizzling pan.
Working quickly, arrange onion, zucchini and tomato wedges
on top. Return to oven immediately. Roast, without opening the
door, for 15 minutes or until vegetables are tender and the
batter is golden and puffed. Add mini Roma tomatoes and cook
for a further 5 minutes or until tomatoes are beginning to
blister. Sprinkle with basil. Cut into pieces. Serve.