Slice the courgettes at an angle, each one into about 6 pieces. Heat a little olive oil in a shallow pan, enough to cover the bottom plus a bit more.
Add the courgettes then cover and cook for about 20 minutes over a low heat, stirring from time to time, until golden and starting to turn brown on their cut edges.
Lift the vegetables out with a slotted spoon and squeeze the lemon juice in to the pan. Scrape and stir in any sticky bits from the bottom. Throw in the basil leaves and season.