Ingredients
- 1 pre-rolled butter puff pastry sheet
- 2 tablespoons thyme leaves
- 1 egg, beaten
- 1 large bunch kale, finely chopped
- 1 tablespoon olive oil
- 1 onion, thinly sliced
- 1 teaspoon brown mustard seeds
- Salt and freshly ground black pepper
- Small handful chopped flat-leaf parsl...
