Fill and boil your kettle, then fill a large pan with the boiling water, topping it up if needed, and add a pinch of salt. Pop the pan on the hob, cover and bring back to the boil. When the water is boiling, add the penne and simmer for 8 mins, till tender but still with a bit of bite. Ladle out a mugful of the starchy cooking water and set that aside, then drain the pasta. Rinse it with cold water. Set aside.
While the pasta cooks, peel and finely chop the onions. Peel and thinly slice the garlic. Halve the chilli, scraping out the seeds and white pith if you prefer less heat. Finely chop the chilli. Trim the dry end off the broccoli. Chop the head into small florets and dice the stalk. Trim the ends off the courgettes and dice them to match the broccoli. Dice the tomatoes. Strip the kale leaves of their stalks and shred the leaves.
Pop the empty pasta pan back onto the hob and warm it to a medium heat. Add 2 tbsp olive oil. Add the onion, garlic, chilli and courgettes. Season with salt, pepper and 1 tbsp Italian herb blend. Fry for 10 mins, stirring occasionally, till the veg are glossy and starting to soften.
Stir the broccoli, tomatoes and kale into the pan. Fry for 10 mins, stirring occasionally, till the veg have softened.
While the veg cook, pick the mint leaves and thinly slice them. Grate the zest off the lemon.
Tip the pasta into the pan of veg, along with the reserved cooking water. Stir turn the heat down to medium-low and warm through for 2-3 mins, till the water has been absorbed.
Stir the mint and lemon zest into the pasta and veg. Squeeze in a little lemon juice. Taste and add more salt, pepper or lemon juice if needed. Divide the dish between warm bowls and serve.