Fill and boil your kettle. Peel and thinly slice the red onion. Halve the cherry tomatoes. Halve the chilli, scraping out the seeds and white pith for less heat (or leave them in if you prefer something spicy), and finely chop it.

Fill a large pan with hot water from the kettle, topping it up with more water if you need to. Add a pinch of salt, cover and set on a high heat to come to the boil.

Warm a deep frying pan on a high heat for 2 mins. Add ½ tbsp olive oil and the beef strips. Stir fry for 4-5 mins till the strips are browned all over.

While the beef fries, check the pan of water. It should be boiling by now, so add the spaghetti and simmer for 8 mins till the spaghetti is cooked but still has some bite.

Scoop the beef out of the pan onto a plate. Add another ½ tbsp olive oil to the pan. Add the onion, season with salt and pepper, and fry, stirring often for 5-6 mins till just starting to brown. If the onion colours too quickly, turn the heat down a little.

Add the cherry tomatoes and chilli to the pan and fry, stirring often, for 4-5 mins till the tomatoes have softened.

Scoop a mugful of water out of the spaghetti pan (mind your fingers, or use a ladle). Drain the pasta.

Add the beef back to the frying pan and spoon in half the jar of pesto. Toss to mix. Add the spaghetti and half the rocket. Toss to mix. Divide the beef pesto pasta between a couple of warm plates. Top with the remaining rocket and tear over the basil leaves to serve.